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The Wondfo 2019-nCoV Antigen Test (Lateral Flow Method) is a visually read lateral flow immunoassay test intended for the qualitative detection of SARS-CoV-2 virus nucleocapsid protein antigen directly in anterior nasal swab specimens from individuals with signs and symptoms of COVID-19.

This test is for non-prescription home use by individuals aged 14 years or older testing themselves, or adults testing individuals aged 2 years or older.

All negative results are presumptive. Symptomatic individuals with an initial negative test result must be re-tested once between 48 and 72 hours after the first test using either an antigen test or a molecular test for SARS-CoV-2. Negative results do not rule out SARS-CoV-2 infections or other pathogens and should not be used as the sole basis for treatment. Positive results do not rule out co-infection with other respiratory pathogens.

This test is not a substitute for visits to a healthcare provider or appropriate follow-up and should not be used to determine any treatments without provider supervision. Individuals who test negative and experience continued or worsening COVID-19 like symptoms, such as fever, cough and/or shortness of breath, should seek follow up care from their healthcare provider.

The performance characteristics for SARS-CoV-2 were established from April, 2023 to February, 2024 when SARS-CoV-2 Omicron was dominant. Test accuracy may change as new SARS-CoV-2 viruses emerge. Additional testing with a lab-based molecular test (e.g., PCR) should be considered in situations where a new virus or variant is suspected.

The Wondfo 2019-nCoV Antigen Test (Lateral Flow Method) is a lateral flow immunoassay intended for non-prescription home use qualitative detection of nucleocapsid protein antigen directly in anterior nasal swab specimens from individuals with signs and symptoms of COVID-19 within the first five (5) days of symptom onset. Results are for the identification of SARS-CoV-2 nucleocapsid protein antigen. The test cassette in the test kit is assembled with a test strip in a plastic housing that contains a nitrocellulose membrane with two lines: a test line (T line) and a control line (C line).

The device is for in vitro diagnostic use only.

The Wondfo 2019-nCoV Antigen Test (Lateral Flow Method) consists of the following components:

• . Tube Holder (located in kit box)
• Test Cassette ●
• Tube (pre-filled extraction buffer) ●
• Swab ●
• Quick Reference Instructions ●

The provided 510(k) summary for the Wondfo 2019-nCoV Antigen Test (Lateral Flow Method) describes the acceptance criteria and a clinical study demonstrating the device's performance.

Here's a breakdown of the requested information:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria for home-use COVID-19 antigen tests often involve minimum Positive Percent Agreement (PPA) and Negative Percent Agreement (NPA) compared to a highly sensitive molecular comparator. While the document doesn't explicitly state "acceptance criteria" as a separate section with specific thresholds, the clinical performance results can be interpreted against expected standards for such devices. For the purpose of this response, we'll assume the achieved performance in the clinical study is what the manufacturer and FDA found acceptable for market clearance.

2. Sample Size Used for the Test Set and Data Provenance

• Test Set Sample Size: 1032 evaluable subjects within 5 days of symptom onset (from a total of 1053 enrolled subjects).
• Data Provenance: Prospective clinical study conducted between April 2023 and February 2024 at nine (9) clinical sites. The country of origin is not explicitly stated, but the manufacturer is Guangzhou Wondfo Biotech Co., Ltd. in China, and the study was likely conducted with data collected in alignment with international regulatory standards for medical device submissions.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

The document states that the ground truth was established using an "FDA-cleared highly sensitive molecular comparator method." This implies that the ground truth was derived from the result of a molecular test, not directly by a panel of human experts reviewing the cases. Therefore, information on the number and qualifications of experts for ground truth establishment for the clinical test set is not applicable in this context, as the comparator method serves as the ground truth.

4. Adjudication Method for the Test Set

The document does not describe an explicit adjudication method for the test set results. The comparison is made between the Wondfo 2019-nCoV Antigen Test and an "FDA-cleared highly sensitive molecular comparator method." It is implied that the results of the molecular comparator method are taken as the definitive ground truth without further adjudication.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

This section is not applicable as the Wondfo 2019-nCoV Antigen Test is a visually read lateral flow immunoassay intended for non-prescription home use. It is not an AI-assisted diagnostic device, nor is it designed for interpretation by multiple expert readers in an MRMC study setting. The device is a standalone test read by lay users.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done

Yes, a standalone performance study was conducted. The clinical study described in section 6 and the non-clinical performance studies (sections 5.1-5.5) represent the standalone performance of the test as it would be used by a lay user without "human-in-the-loop" expert interpretation beyond the visual reading of the test lines by the user.

7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)

The ground truth for the clinical study was established by an FDA-cleared highly sensitive molecular comparator method (e.g., PCR), which is considered the gold standard for SARS-CoV-2 detection.

8. The Sample Size for the Training Set

The document does not explicitly mention a "training set" in the context of machine learning or AI. This device is a lateral flow immunoassay, a biochemical test, not an AI/ML-based diagnostic. Therefore, the concept of a training set for an algorithm is not applicable. The device's manufacturing and design would have involved internal validation and optimization, but not in the sense of an algorithm training on a dataset.

9. How the Ground Truth for the Training Set was Established

As explained in point 8, the concept of a training set and its ground truth in the AI/ML sense is not applicable to this lateral flow immunoassay device. The device's performance is based on its biochemical reactions and physical design, which are validated through non-clinical and clinical studies.

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The SAFElife™ Fentanyl Urine Home Test (Cassette) is a competitive binding, lateral flow immunochromatographic assay for qualitative detection of Fentanyl in human urine at cutoff concentration of 1 ng/mL.

For in vitro diagnostic use. For Over The Counter (OTC) use.

The test provides only preliminary test results. To obtain a confirmed analytical result, a more specific alternate chemical method must be used. Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Tandem Mass Spectrometry (LC/MS-MS) is the recommended confirmatory method.

The SAFElife™ Fentanyl (FTY) Urine Test Cassette is a competitive binding, lateral flow immunochromatoqraphic assay for qualitative detection of Fentanyl (FTY) in human urine at cutoff concentration of 1 ng/mL.

For in vitro diagnostic use.

lt is not intended to distinquish between prescription drug or abuse of the drug. Clinical consideration and professional judgment should be applied to the drug of abuse test result, particularly in evaluating a preliminary positive result.

The test provides only preliminary test results. To obtain a confirmed analytical result, a more specific alternate chemical method must be used. Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Tandem Mass Spectrometry (LC/MS-MS) is the recommended confirmatory method.

The SAFElife™ T-Dip Fentanyl Urine Home Test (Dip Card) is a competitive binding, lateral flow immunochromatographic assay for qualitative detection of Fentanyl in human urine at cutoff concentration of 1 ng/mL.

For in vitro diagnostic use. For Over The Counter (OTC) use.

The test provides only preliminary test results. To obtain a confirmed analytical result, a more specific alternate chemical method must be used. Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Tandem Mass Spectrometry (LC/MS-MS) is the recommended confirmatory method.

The SAFElife™ T-Dip Fentanyl (FTY) Urine Test Panel is a competitive binding, lateral flow immunochromatographic assay for qualitative detection of Fentanyl (FTY) in human urine at cutoff concentration of 1 ng/mL.

For in vitro diagnostic use.

It is not intended to distinguish between prescription drug or abuse of the drug. Clinical consideration and professional judgment should be applied to the drug of abuse test result, particularly in evaluating a preliminary positive result. The test provides only preliminary test results. To obtain a confirmed analytical result, a more specific alternate chemical must be used. Chromatography/Mass Spectrometry (GC/ MS) or Liquid Chromatography/Tandem Mass Spectrometry (LC/MS-MS) is the recommended confirmatory method.

The Wondfo SAFElife™ Fentanyl Tests are immunoassays intended for the qualitative detection of fentanyl in human urine. Each Wondfo SAFElife™ Fentanyl Test consists of a Test Device in format of Cassette or Dip Card, and a package insert. Each Test Device is sealed with sachets of desiccant in an aluminum pouch.

Acceptance Criteria & Study Analysis for SAFElife™ Fentanyl Urine Home Test

The SAFElife™ Fentanyl Urine Home Test (and its variants) are competitive binding, lateral flow immunochromatographic assays for qualitative detection of Fentanyl in human urine at a cutoff concentration of 1 ng/mL. The device provides preliminary test results, with confirmation requiring a more specific alternate chemical method like GC/MS or LC/MS-MS.

1. Acceptance Criteria and Reported Device Performance

The provided documentation does not explicitly state formal acceptance criteria in the typical "pass/fail" format for each performance characteristic. However, the study results implicitly demonstrate the device's acceptable performance based on standard expectations for qualitative drug screening tests.

Given the information, we can infer the acceptance criteria and compare them to the reported performance:

2. Sample Size Used for the Test Set and Data Provenance

• Precision Studies Test Set:

  • For each of the 9 concentration levels, 50 tests were performed for each of the 3 device lots.
  • Total tests for Precision (Cassette): 9 concentrations * 50 tests/concentration * 3 lots = 1350 tests.
  • Total tests for Precision (Dip Card): 9 concentrations * 50 tests/concentration * 3 lots = 1350 tests.
  • Data Provenance: The samples were "prepared by spiking fentanyl in negative samples." The document does not specify the country of origin but implies laboratory-prepared controlled samples. The study is prospective in nature as samples were prepared for the purpose of the study.

• Interference Test Set: Not explicitly stated as a single "test set" size. "These urine samples were tested using three batches of each device." The number of samples for each interferent tested at specific concentrations (drug-free and fentanyl-spiked) is not quantified.

  • Data Provenance: Laboratory-prepared controlled samples with spiked substances. Most likely retrospective analysis of prepared samples.

• Specificity (Cross-Reactivity) Test Set: Similar to interference, not a single "test set" size. "drug metabolites and other components that are likely to interfere in urine samples were tested using three batches of device." The number of individual compounds tested is large (dozens of fentanyl analogs and many other opioids/non-opioids).

  • Data Provenance: Laboratory-prepared controlled samples with spiked substances. Most likely retrospective analysis of prepared samples.

• Effect of Urine Specific Gravity and pH Test Set: Not explicitly stated as a single "test set" size. "These samples were tested using three lots of device." Samples were prepared by spiking target fentanyl at -50% and +50% Cut-Off levels across specific gravity and pH ranges.

  • Data Provenance: Laboratory-prepared controlled samples. Most likely retrospective analysis of prepared samples.

• Method Comparison Studies Test Set:

  • Cassette: 84 "unaltered clinical samples."
  • Dip Card: 84 "unaltered clinical samples." (It's unclear if these are the same 84 samples for both formats or separate sets of 84).
  • Data Provenance: "unaltered clinical samples." The country of origin is not specified, but the clinical nature suggests they were collected from human subjects. The study appears to be retrospective as these samples were "blind labeled" and then tested.

• Lay-user Study Test Set:

  • For each device format (Cassette and Dip Card), 7 different concentration levels were tested, with 20 samples per concentration.
  • Total samples per device format: 7 concentrations * 20 samples/concentration = 140 samples.
  • Total samples overall: 140 samples (Cassette) + 140 samples (Dip Card) = 280 samples.
  • Data Provenance: Samples were "prepared at the following concentrations by spiking fentanyl into drug free-pooled urine specimens." The samples were then blind-labeled and randomized. The study is prospective since samples were prepared for the study.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

• Precision, Interference, Specificity, Effect of SG/pH, Lay-user Studies: The "ground truth" (actual fentanyl concentration or absence) was established by LC/MS (Liquid Chromatography/Mass Spectrometry) for all spiked samples. This is a highly accurate analytical method, and human experts are not directly establishing the ground truth in terms of visual interpretation for these studies. The LC/MS results are considered the definitive quantitative measurement.
• Method Comparison Studies: The ground truth for the 84 "unaltered clinical samples" was established by LC/MS. The document states, "The samples were blind labeled and compared to LC/MS results." No human experts (e.g., pathologists, radiologists) were involved in establishing the ground truth for these quantitative drug levels.

4. Adjudication Method for the Test Set

The concept of "adjudication" (e.g., 2+1, 3+1) typically applies to situations where multiple human readers are interpreting results and their agreement/disagreement needs to be resolved. In this case, the device output is a qualitative (positive/negative) result based on a visual line, and the ground truth is established by a quantitative analytical method (LC/MS).

• For the Precision studies, the results are quantitative counts of "positive" or "negative" for each lot and concentration, implying a direct read of the test.
• For the Method Comparison Studies, the rapid test results from the operators were directly compared to the LC/MS results. Discordant results are simply listed. No adjudication process is described for resolving discrepancies in the rapid test readings themselves among different operators, but rather the discrepancy is noted between the rapid test result and the LC/MS ground truth.
• For the Lay-user study, each participant (lay person) used one device and provided their result. The comparison was then made between the lay person's result and the LC/MS confirmed concentration. The study report only mentions "Lay person results" (No. of Positive / No. of Negative) implying their individual readings were collected and analyzed for correctness.

Therefore, an adjudication method in the traditional sense (e.g., expert panel review to resolve conflicting interpretations) was not applied, as the output is a qualitative visual reading compared to an analytical gold standard.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done.

An MRMC study typically compares the performance of multiple human readers on multiple cases, often with and without AI assistance, to determine if the AI improves human reader performance (e.g., sensitivity, specificity, efficiency). The studies presented here focus on the standalone performance of the device itself (precision, analytical performance, and comparison to LC/MS) and a lay-user study for ease of use. There is no mention of human readers being compared with and without AI assistance.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done

Yes, the primary studies presented are essentially standalone performance studies for the device.

The SAFElife™ Fentanyl Urine Home Test is a qualitative lateral flow immunoassay. Its "algorithm" is the biochemical reaction that produces a visual line. The precision studies, interference studies, specificity studies, effect of SG/pH studies, and method comparison studies all evaluate the device's ability to correctly classify samples as positive or negative based on its inherent properties, without human interpretation being the primary variable of interest for method comparison against LC/MS.

While the "reading" of the line is ultimately done by a human (either a trained operator in the method comparison or a lay-user in that specific study), the performance characteristics described (e.g., sensitivity at cutoff, cross-reactivity) are intrinsic to the device's chemical and physical design, functioning as an "algorithm-only" or "device-only" performance evaluation against a gold standard. The lay-user study specifically tests the human-in-the-loop aspect for OTC use, but the core analytical performance is evaluated as standalone.

7. The Type of Ground Truth Used

The primary ground truth used across all analytical performance studies (Precision, Interference, Specificity, Effect of SG/pH, and Method Comparison) and the Lay-user study was Liquid Chromatography/Mass Spectrometry (LC/MS).

LC/MS is a highly sensitive and specific analytical technique used to identify and quantify substances in complex mixtures, making it a robust "gold standard" for determining precise drug concentrations in urine samples.

8. The Sample Size for the Training Set

The document does not describe a "training set" in the context of an algorithm that learns from data. This device is a biochemical immunoassay, not a software-based AI algorithm that requires a training phase. Its performance is determined by its physical and chemical design, not by learning from a dataset.

Therefore, the concept of a "training set" is not applicable to this device.

9. How the Ground Truth for the Training Set Was Established

As noted above, a "training set" is not applicable because this is a biochemical immunoassay, not a machine learning algorithm.

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Wondfo T-Dip® Multi-Drug Urine Test Panel tests are competitive binding, lateral flow immunochromatographic assays for qualitative and simultaneous detection of Amphetamine, Secobarbital, Oxazepam, Cocaine, 2- ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, Methylenedoxymethamphetamine, Morphine, Methadone, Oxycodone, Phencyclidine, Propoxyphene, Nortriptyline and Cannabinoids in human urine at the cutoff concentrations of:

Wondfo T-Dip® Multi-Drug Urine Test Panel offers any combinations from 2 to 15 drugs of abuse tests but only one cutoff concentration under same drug condition will be included per device. It is for in vitro diagnostic use only. It is intended for OTC use.

The tests may yield positive results for the prescription drugs Buprenorphine, Oxazepam, Secobarbital, Propoxyphene, and Oxycodone when taken at or above prescribed doses. It is not intended to distinguish between prescription use or abuse of these drugs. Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly in evaluating a preliminary positive result.

The tests provide only preliminary results. To obtain a confirmed analytical result, a more specific alternate chemical method must be used. GC/MS or LC/MS is the recommended confirmatory method.

Wondfo T-Dip® Multi-Drug Urine Test Panel Rx tests are competitive binding, lateral flow immunochromatographic assays for qualitative and simultaneous detection of Amphetamine, Secobarbital, Oxazepam, Cocaine, 2- ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, Methylenedioxymethamphetamine, Morphine, Methadone, Oxycodone, Phencyclidine, Propoxyphene, Nortriptyline and Cannabinoids in human urine at the cutoff concentrations of:

Wondfo T-Dip® Multi-Drug Urine Test Panel Rx offers any combinations from 2 to 15 drugs of abuse tests but only one cutoff concentration under same drug condition will be included per device. It is for in vitro diagnostic use only. It is intended for prescription use.

The tests may yield positive results for the prescription drugs Buprenorphine, Oxazepam, Secobarbital, Propoxyphene, and Oxycodone when taken at or above prescribed doses. It is not intended to distinguish between prescription use or abuse of these drugs. Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly in evaluating a preliminary positive result.

The tests provide only preliminary results. To obtain a confirmed analytical result, a more specific alternate chemical method must be used. GC/MS or LC/MS is the recommended confirmatory method.

The Wondfo T-Dip® Multi-Drug Urine Test Panel and Wondfo T-Dip® Multi-Drug Urine Test Panel Rx are rapid, single-use in vitro diagnostic devices. Each test kit contains a test device in one pouch. One pouch contains a test T-Dip® panel and two desiccants, and a package insert. The Wondfo T-Dip® Multi-Drug Urine Test Panel is intended for over-the-counter use and the Wondfo T-Dip® Multi-Drug Urine Test Panel Rx is intended for prescription use.

The provided text details the performance characteristics of the "Wondfo T-Dip® Multi-Drug Urine Test Panel" and its prescription counterpart, "Wondfo T-Dip® Multi-Drug Urine Test Panel Rx." The acceptance criteria and the studies that prove the device meets these criteria are outlined through a series of analytical and comparison studies.

Acceptance Criteria and Reported Device Performance

The core acceptance criterion for this device is its ability to qualitatively detect various drugs and their metabolites in human urine at predefined cutoff concentrations. The studies demonstrate the device's precision, stability, and specificity, showing that it accurately identifies samples above the cutoff as positive and below the cutoff as negative.

Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are implicitly defined by the cutoff concentrations for each drug and the results of the precision and comparison studies. For the precision studies, the acceptance criteria would be near 100% agreement for samples significantly above and below the cutoff, with some expected variability around the cutoff. For the comparison studies, high agreement with GC/MS or LC/MS results is the criterion.

Note: The precision study results are presented as "X-/Y+" which means X negative results and Y positive results out of 50 total tests. The percentage reported here is P/N out of 50 at the cutoff concentration. The comparison study performance section summarizes Viewer A's agreement, and lists discordant results separately.

Study Information

The studies described are a combination of analytical performance evaluations (precision, linearity, stability, interference, specificity) and method comparison studies, along with a lay-user study.

1. Sample sizes used for the test set and the data provenance:

   • Precision Studies: For each drug and cutoff level, samples were prepared at -100%, -75%, -50%, -25%, cutoff, +25%, +50%, +75%, and +100% of the cutoff concentration. For each concentration, 50 tests were performed for each of three lots, meaning 150 tests per concentration level per drug.
   • Comparison Studies: For each drug and cutoff level, 80 unaltered urine samples (40 negative and 40 positive based on LC/MS or GC/MS) were used. So, a total of 80 samples per drug per cutoff level were tested by three operators.
   • Lay-user Study: A total of 280 participants were recruited. Urine samples were prepared at -100%, +/-75%, +/-50%, +/-25% of the cutoff. These samples were split into individual containers and blind-labeled. For Configuration 1 (AMP 500, MET 500, MOP 300, COC 150), 94 males and 46 females participated. For Configuration 2 (AMP 1000, MET 1000, OPI 2000, COC 300), 88 males and 52 females participated. Assuming each participant tested one sample for each drug in their respective configuration, and samples are distributed across concentration levels, the number of tests is significant. For each drug, 20 samples were tested at each of the 7 concentration levels (-100%, -75%, -50%, -25%, +25%, +50%, +75%). Total 140 samples per drug for the lay-user study.
   • Data Provenance: Not explicitly stated, but given it's a 510(k) submission for a device from Guangzhou Wondfo Biotech Co., Ltd., the studies were likely conducted internally or by affiliated labs. The samples for precision and specificity were prepared by spiking known concentrations of drugs into drug-free urine. The comparison study used "unaltered urine samples." The lay-user study used "drug-free-pooled urine specimens" spiked with drugs. No specific country of origin for the "unaltered urine samples" or participants is mentioned outside the manufacturer's location. The studies are retrospective as they involve collected urine samples and controlled spiking.

2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g., radiologist with 10 years of experience):

   • For precision, specificity, and comparison studies, the ground truth was established by LC/MS or GC/MS (Liquid Chromatography/Mass Spectrometry or Gas Chromatography/Mass Spectrometry). These are highly accurate analytical chemistry methods often used as gold standards for drug detection and quantification. The document does not specify human experts for establishing ground truth from these methods; the machines and their operators are implicitly considered the truth-tellers.
   • For the lay-user study, the ground truth was also established by LC/MS or GC/MS for the prepared samples.

3. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

   • For the precision studies, tests were performed over 25 days, two runs per day, using three lots of test panels. The results for each lot and concentration are reported directly (e.g., "10-/40+"), indicating direct observation of results. No explicit human adjudication method for discrepancies is mentioned for these specific quantitative precision results, suggesting a clear positive/negative line based on instrumentation.
   • For the comparison studies, three operators (Viewers A, B, and C) independently read the results. Discordant results are noted and tabulated for each viewer and drug. There is no mention of an adjudication process (e.g., 2+1 or 3+1 rule) to resolve these discrepancies; instead, the individual viewer's result and the LC/MS or GC/MS ground truth are presented.
   • For the lay-user study, results are reported as the number of negative/positive readings at specific concentrations. It's implicit that each participant provided their own reading, and there was no inter-reader adjudication mentioned.

4. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:

   • No MRMC comparative effectiveness study was done involving AI. This device is a rapid, lateral flow immunochromatographic assay, which is a qualitative chemical test, not an AI-powered diagnostic device. The "Viewers" mentioned in the comparison studies are human operators reading the result of a chemical test, not an AI.

5. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:

   • This is not applicable, as the device is a chemical test that produces a visually interpretable result (colored bands). It does not involve an algorithm or AI. The "precision study" and "comparison study" essentially serve as standalone performance evaluations of the device itself, without human interpretation variability being the primary focus, but rather the device's accuracy in producing a result. The "lay-user study" introduces human-in-the-loop (lay users interpreting results) but it's not an AI-assisted loop.

6. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):

   • The ground truth used for all performance studies (precision, comparison, and lay-user) was analytical confirmation by LC/MS or GC/MS. These are considered definitive laboratory methods.

7. The sample size for the training set:

   • This is not applicable. The device is a diagnostic test kit (immunochromatographic assay), not an AI algorithm that requires a training set.

8. How the ground truth for the training set was established:

   • This is not applicable, as there is no training set for a chemical diagnostic device.

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Wondfo T-Cup® Multi-Drug Urine Test Cup tests are competitive binding, lateral flow immunochromatographic assays for qualitative and simultaneous detection of Amphetamine, Secobarbital, Oxazepam, Cocaine, 2ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, Methylenedioxymethamphetamine, Morphine, Methadone, Oxycodone, Phencyclidine, Propoxyphene, Nortriptyline and Cannabinoids in human urine at the cutoff concentrations of:

Wondfo T-Cup® Multi-Drug Urine Test Cup offers any combinations from 2 to 15 drugs of abuse tests but only one cutoff concentration under same drug condition will be included per device. It is for in vitro diagnostic use only,

The tests may yield positive results for the prescription drugs Buprenorphine, Oxazepam, Secobarbital, Propoxyphene, and Oxycodone when taken at or above prescribed doses. It is not intended to distinguish between prescription use or abuse of these drugs. Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly in evaluating a preliminary positive result.

The tests provide only preliminary results. To obtain a confirmed analytical result, a more specific alternate chemical method must be used. GC/MS or LC/MS is the recommended confirmatory method.

Wondfo T-Cup® Multi-Drug Urine Test Cup are immunochromatographic assays that use a lateral flow system for the qualitative detection of Amphetamine, Buprenorphine, Secobarbital, Oxazepam, Cocaine, 2ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine,Methamphetamine, Methylenedioxymethamphetamine, Morphine, Methadone, Oxycodone, Phencyclidine, Propoxyphene, Nortriptyline and Cannabinoids in human urine. Each T-Cup® Multi-Drug Urine Test Cup device consists of a test cup and a package insert. Each test cup is sealed with two sachets of desiccant in an aluminum pouch.

This document is a 510(k) Summary for the Wondfo T-Cup® Multi-Drug Urine Test Cup, a rapid diagnostic device for detecting various drugs of abuse in urine. It describes the device's performance characteristics and a "lay-user study" that can be interpreted as a clinical study for a consumer-facing device.

Here's an analysis of the acceptance criteria and study data based on the provided text, framed to address your questions for an AI/ML device where applicable (though this device is an in-vitro diagnostic, not an AI/ML system):

Acceptance Criteria and Device Performance for Wondfo T-Cup® Multi-Drug Urine Test Cup

Since this is an in-vitro diagnostic device and not an AI/ML system, the "acceptance criteria" are typically defined by precision, specificity, linearity (if applicable), stability, and method comparison studies against a gold standard (LC/MS or GC/MS). The study described for the "lay-user" simulates a real-world use case for intended over-the-counter (OTC) use and provides data on how lay users interpret the results around the device's cut-off.

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" in a pass/fail form for the lay-user study. Instead, it presents the results as percentages of correct results at different concentrations relative to the cutoff. For in-vitro diagnostics like this, the implicit acceptance criteria for performance usually revolve around high agreement with confirmed analytical methods (LC/MS or GC/MS), particularly around the cutoff concentrations, and demonstrating usability for the intended user (lay-user in this case).

The performance data for the "lay-user study" is provided for various drugs at different concentrations relative to the cutoff. A "correct result" implies agreement with the LC/MS or GC/MS ground truth.

The percentage of correct results at concentrations -100%, -75%, -50%, +50%, +75% demonstrated 100% accuracy in the lay-user study for most drugs. Performance around the cutoff (at +/- 25% of cutoff) showed some misclassifications, typically around 85-95% accuracy.

2. Sample Size Used for the Test Set and Data Provenance

The primary test set for the device's performance is referred to as "Precision studies," "Comparison Studies," and "Lay-user study."

• Precision Studies: For each drug and each concentration (-100% cutoff, -75% cutoff, -50% cutoff, -25% cutoff, +25% cutoff, +50% cutoff, +75% cutoff, and +100% cutoff), tests were performed two runs per day for 25 days. This means a total of 50 tests per concentration per lot. With 3 lots, this is 150 tests per concentration level per drug. The total number of concentrations varied per drug, but on average there are roughly 8 concentrations, so 1200 individual tests per drug type.
• Comparison Studies (In-House): 80 unaltered urine samples (40 negative and 40 positive) were used. The provenance of this data (e.g., country of origin) is not explicitly stated but implied to be from an internal study ("performed in-house"). The samples were retrospective as they were prepared with spiked drug concentrations and used as "unaltered urine samples."
• Lay-User Study:
  • Configuration 1 (AMP 500, MET 500, MOP 300, COC 150): 89 males and 51 females participated, totaling 140 participants.
  • Configuration 2 (AMP 1000, MET 1000, MOP 2000 (OPI), COC 300): 84 males and 56 females participated, totaling 140 participants.
  • Each participant was given 1 blind labeled sample. For each drug, sample concentrations were -100%, +/-75%, +/-25% of the cutoff. Given there are 7 concentrations listed for each drug in the lay-user study tables, and a total of 20 samples per concentration level, this indicates 140 samples per drug (7 concentrations x 20 samples/concentration).
  • Data provenance: "Urine samples were prepared... by spiking drug(s) into drug free-pooled urine specimens." This indicates the samples were synthetic/controlled (spiked), not necessarily from real patients. The study was likely conducted in China, given the manufacturer's location (Guangzhou Wondfo Biotech Co., Ltd.). The study is prospective in the sense that participants were recruited to read the tests.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications

The ground truth for all studies (Precision, Comparison, and Lay-User) was established using LC/MS or GC/MS (Liquid Chromatography-Mass Spectrometry or Gas Chromatography-Mass Spectrometry). These are highly accurate and widely accepted analytical methods for chemical substance identification and quantification, considered the "gold standard" for drug testing. No human experts are explicitly mentioned as establishing the initial ground truth for the drug concentrations, as this is laboratory methodologically determined.

For the Comparison Studies (In-House), "three operators" ran the samples. Their qualifications are not specified beyond being "operators," but they would be trained lab personnel capable of correctly performing the tests and interpreting the results.

4. Adjudication Method for the Test Set

• Precision Studies: No explicit adjudication method is mentioned for individual readings within daily runs. The overall results are summarized by tallying positive/negative results across all runs and lots.
• Comparison Studies (In-House): "Operators ran 80 (40 negative and 40 positive) unaltered urine samples." The results were then compared to LC/MS or GC/MS. The tables show results for Viewer A, Viewer B, and Viewer C, implying three independent readers/operators performed and reported the results. Discordant results are individually listed for each viewer against the LC/MS result, indicating that each viewer's interpretation was recorded, and there was no internal adjudication between the viewers before comparison to the ground truth.
• Lay-User Study: "Each participant was provided with... 1 blind labeled sample and a device." This suggests no formal adjudication among lay-users. Each participant's reading was taken as their individual result and then compared against the LC/MS or GC/MS ground truth.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, and its effect size

No, a traditional MRMC comparative effectiveness study was not done in the context of human readers improving with AI vs. without AI assistance. This device is an in-vitro diagnostic, not an AI-assisted diagnostic.

However, the "Comparison Studies" with three "Viewers" (human operators) against the LC/MS/GC/MS ground truth, and the "Lay-User Study" where multiple lay participants interpreted the results, do resemble aspects of MRMC studies in that they evaluate multiple readers (operators/lay users) across multiple cases (samples). The "effect size" here would be the agreement of the device, as interpreted by human readers, with the gold standard. The tables show detailed agreement and disagreement for various drugs and concentrations. For example, in the "Comparison Studies" for AMP 500, Viewer A had 2 false positives near cutoff negative and 30 true positives near cutoff positive, compared to LC/MS.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done

This question is not applicable as the device is not an algorithm or AI. It is a rapid diagnostic test that produces a visual result that must be interpreted by a human user. Its performance is inherently tied to human interpretation.

7. The Type of Ground Truth Used

The type of ground truth used for all performance evaluations (precision studies, in-house comparison studies, and lay-user studies) was confirmed analytical results from LC/MS or GC/MS (Liquid Chromatography-Mass Spectrometry or Gas Chromatography-Mass Spectrometry). This is a highly objective and quantitative chemical analysis, serving as the definitive measurement of drug concentration in the urine samples.

8. The Sample Size for the Training Set

This question is not applicable. This is an in-vitro diagnostic device (a chemical test) and does not involve AI/ML requiring a training set in the conventional sense. The "training" of the device is through its chemical formulation and manufacturing process, optimized through R&D, rather than data-driven machine learning.

9. How the Ground Truth for the Training Set Was Established

Not applicable, as there is no "training set" in the context of AI/ML for this device. The development of the test's performance characteristics (e.g., sensitivity, specificity, cutoff levels) would have been established during the research and development phase of the immunochromatographic assay, typically through extensive chemical and biological experimentation to optimize reagent concentrations and reaction conditions.

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Preview® Digital Pregnancy Test is intended for the qualitative detection of human chorionic gonadotropin (hCG) in urine, as an aid in early detection of pregnancy.

Preview® Digital Pregnancy Test is designed to be tested in dip and midstream modes. Preview® Digital Pregnancy Test consists of a single test strip encased in plastic device housing, with an absorbent tip. The device is in a ready-to-use format and no longer requires assembly before use.

Here's a breakdown of the acceptance criteria and the study details for the Preview Digital Pregnancy Test, based on the provided text:

Acceptance Criteria and Device Performance

The acceptance criteria for qualitative pregnancy tests typically revolve around their sensitivity and specificity (accuracy in detecting or ruling out pregnancy). While explicit "acceptance criteria" are not listed as a separate section with numerical targets, the document demonstrates the device's performance against expected standards for sensitivity (25 mIU/mL) and specificity (100%).

Study Information

2. Sample sizes used for the test set and the data provenance:

• Analytical Sensitivity:
  • 30 samples per hCG concentration level (0, 5, 12.5, 15, 18.75, 25, 50, 100 mIU/mL) for each of 3 lots (total 30 x 8 x 3 = 720 tests for dip and 720 tests for in-stream).
  • Provenance: Samples were prepared "in negative urine pool" and "calibrated against the WHO 4th IS for hCG", suggesting laboratory-prepared (synthetic/spiked) samples.
• Analytical Specificity:
  • 300 urine samples (100 each from pre-menopausal, peri-menopausal, and post-menopausal non-pregnant females).
  • Provenance: Retrospective, collected from normal, non-pregnant females. Country of origin not specified, but the submitter is from China.
• Hook Effect:
  • Samples spiked with hCG concentrations from 6,250 to 500,000 mIU/mL. Specific number of samples per concentration not given, but it implies a range of samples tested across these concentrations.
  • Provenance: Laboratory-prepared (spiked) negative urine samples.
• Interfering Substance:
  • Urine samples containing 0, 5, 25, and 100 mIU/mL hCG spiked with each interfering substance. Specific number of samples per substance not given.
  • Provenance: Laboratory-prepared (spiked) urine samples.
• Precision:
  • 50 replicates per hCG concentration (0, 5, 12.5, 15, 18.75, 25, 50, 100, 1000 mIU/mL) for each of 3 lots (total 50 x 9 x 3 = 1350 tests for dip and 1350 tests for in-stream).
  • Provenance: Laboratory-prepared (spiked) negative human urine samples.
• Method Comparison Study:
  • 300 urine samples collected from women presenting to test for pregnancy (approximately half suspected pregnant).
  • Provenance: Prospective collection from unknown locations (likely the submitter's country or chosen clinical sites).
• Lay Person Study (First):
  • 200 women for self-testing.
  • Provenance: Prospective, collected from women. "Varying educational and occupational backgrounds from three sites were chosen". Country of origin not specified.
• Lay Person Study (Second):
  • 200 women for self-testing using spiked samples (100 subjects for 5 mIU/mL hCG and 100 for 25 mIU/mL hCG).
  • Provenance: Laboratory-prepared (spiked) negative urine sample pools. "Each testing site had a study administrator to observe or monitor the studies". Country of origin not specified.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

• Analytical Sensitivity, Specificity, Hook Effect, Interfering Substances, Precision: The ground truth was established by the known concentrations of hCG in the reference standards or spiked samples, traceable to the WHO 4th IS for hCG. This does not involve human experts for ground truth establishment.
• Method Comparison Study: The ground truth for the 300 clinical samples was established by the results of the "predicate device". There's no mention of independent expert adjudication for these samples.
• Lay Person Study (First): The ground truth was established by "professional testing" of the samples. The number and qualifications of these professionals are not specified.
• Lay Person Study (Second): The ground truth was established by the known spiked concentration of hCG (0, 5 mIU/mL, 25 mIU/mL).

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:

• None specified for any part of the study in terms of expert adjudication.
  • For the analytical studies, ground truth was by reference standard/known concentration.
  • For the method comparison, the predicate device served as the reference.
  • For the first lay person study, "professional testing" served as reference, but the method for their consensus or adjudication is not detailed.
  • For the second lay person study, ground truth was by known spike concentration.

5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:

• No MRMC study was performed. This device is a standalone digital pregnancy test, not an AI-assisted interpretation system for human readers. Its output is a direct digital result (effectively an "AI" in the sense of an automated algorithm, but without a human-in-the-loop component for interpretation that would be improved by AI assistance).

6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:

• Yes, this was a standalone performance study. The device itself provides a digital readout (LCD screen) after interpreting the immunochromatographic assay. The "algorithm" is inherent in the device's mechanism to detect and display the presence or absence of hCG, replacing visual interpretation of lines by a human. The lay person study confirms its standalone performance with non-expert users.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):

• Known Reference Standards/Spiked Samples: For analytical sensitivity, Hook effect, interfering substances, and precision studies. These are traceable to the WHO 4th International Standard for hCG.
• Predicate Device Results: For the method comparison study.
• Professional Testing Results: For the first lay person study. (Specifics not provided for how "professional testing" itself established ground truth).
• Known Spiked Sample Concentrations: For the second lay person study.

8. The sample size for the training set:

• Not applicable / Not specified. This device is an immunoassay, not a machine learning model that requires a "training set" in the conventional sense of AI development. Its performance is based on the chemical and optical design of the lateral flow assay and the internal programming to interpret the signal, which is not typically "trained" on data in the same way an AI algorithm is.

9. How the ground truth for the training set was established:

• Not applicable. As explained above, there's no traditional "training set" for this type of IVD device. The design and calibration are based on established immunochemical principles and reference materials.

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Wondfo One Step Fecal Occult Blood Test is a rapid test for the qualitative detection of human occult blood in feces. It is used as an aid in the diagnosis of gastrointestinal(GI) bleeding. The device is suitable for use in laboratories and physician's offices as well as for over the counter use.

For in vitro diagnostic use only. For prescription use and over the counter use.

The Wondfo One Step Fecal Occult Blood Test utilizes double antibodies sandwich immunoassay for the detection of hemoglobin in test samples. The test kit consists of:

Test devices, one test in one pouch. One pouch contains a test cassette and a desiccant. The desiccant is for storage purposes only and is not used in the test procedures.
Collection tubes with 1.5mL extraction buffer solution.
Clean collection papers.
Instructions for use.

Here's a breakdown of the acceptance criteria and study information for the Wondfo One Step Fecal Occult Blood Test, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance:

The document doesn't explicitly state "acceptance criteria" for each performance characteristic. Instead, it presents results that were deemed "acceptable" or demonstrated "substantial equivalence" to the predicate device. Therefore, the table below reflects the reported performance which implies it met the internal acceptance benchmarks.

• 2-8°C: Up to 30 days
• -20°C: Up to 3 months |
  | In-use Stability | Maintain performance for a reasonable in-use period. | Up to 1 hour under various temperature/humidity conditions. |
  | Test Kit Stability | Maintain performance over specified storage periods. | - Accelerated: Estimated 24 months at 4-30°C
• Real Time: Stable for at least 27 months at 4, 10, 20, 30°C. |
  | Transport Stability | Maintain performance after exposure to transport conditions. | Stable up to 35 transport days when stored at -20°C and 40°C. |
  | Interference | No significant interference from common substances. | No significant interference from vegetable extracts, Vitamin C, iron, or horseradish peroxidase. False negatives with 1% toilet cleaner. |
  | Specificity (Hb Variants) | Detect common human hemoglobin variants. | Equivalently recognized HbA, HbS, and HbC. |
  | Specificity (Cross-Reactivity) | No significant cross-reactivity with non-human heme or meat extracts. | No significant interference from non-human hemoglobin or animal meat extracts. |
  | Cut-off | Consistent performance at the established cut-off. | Determined to be 1.35 µg hemoglobin/g stool or 45 ng/mL. Overall Agreement of 99.3% in cut-off study. |
  | Method Comparison | Acceptable overall, positive, and negative percent agreement with predicate. | Overall Combined Sites: Overall 99.6%, Positive 99.2%, Negative 99.7% |
  | Lay-user Study (Own Samples) | High agreement between lay-user and professional results. | Own Samples: 100% agreement between lay-users and professional testers. |
  | Lay-user Study (Spiked Samples) | High agreement between lay-user and professional results for spiked samples. | Spiked Samples: Overall 98% agreement. (2 discrepant results at 37.5 ng/mL). |
  | Lay-user Study (Instructions) | Instructions are easily understood. | All lay users indicated instructions were easily followed. |
  | Reaction Time | Optimal reaction time for accurate results. | Demonstrated as 10 minutes (100% positivity at 50 ng/mL at 10 minutes). |
  | Operator Intensity Reading | Consistency in reading test line intensity across operators. | No statistical significance in analyses by operators for intensity reading. |
  | Specimen Collection Verification | Consistent delivery of specified stool amount by applicator. | Average collected volume of 0.0517g with standard deviation of 0.0027, demonstrating consistency. |

2. Sample Sizes and Data Provenance:

• Precision/Reproducibility:
  • Repeatability: 21 replicates for each of 7 concentrations (total 147 samples). Data provenance is "in house".
  • Reproducibility: 21 replicates for each of 7 concentrations, tested at 3 POC sites, with 3 kit lots, 3 operators, and 5 non-consecutive days each. This would be 21 * 7 * 3 * 3 * 5 = 6615 tests in total across sites for the primary experiment, with reported summarized results from a subset of this (e.g., 735 for lot-to-lot, between-run, between-device, between-site, and 2205 for combined reproducibility). Data provenance: 3 POC sites in the U.S.
• Linearity (Prozone Hook Effect): 5 aliquots for each of 7 concentrations (total 35 samples). Data provenance is "in house".
• Sample Stability: For each condition (room temp, 2-8°C, -20°C): 7 different hemoglobin concentrations, tested repeatedly over time. The exact total sample count for stability studies (especially across all time points and conditions) is not explicitly totaled but would be substantial.
• Interference: 21 aliquots of hemoglobin-negative stool spiked with 7 different Hb concentrations (total 147 samples per interfering substance tested). Tested against various vegetable extracts, vitamin C, iron, horseradish peroxidase, toilet cleaners.
• Specificity (Hb Variants): 21 aliquots for each of 7 concentrations of each Hb variant (HbA, HbS, HbC). (Thus, 21 * 7 * 3 = 441 samples).
• Cross-Reactivity: 21 aliquots of hemoglobin-negative stool spiked with 7 different Hb concentrations (total 147 samples per non-human Hb/meat extract). Tested against 8 non-human hemoglobins and 8 animal meat extracts.
• Cut-off Study: 21 aliquots of each of 7 concentrations (total 147 samples). Tested side-by-side with predicate using the same sample set. Data provenance is "in house".
• Comparison Studies (Method):
  • 407 patient samples.
  • 18 stool samples around the cut-off (purchased).
  • 100 spiked samples.
  • Total 525 samples analyzed in the comparison study tables.
  • Data provenance: Performed at three POC testing sites.
• Lay-user Study:
  • Own stool samples: 100 lay users each testing their own stool sample (100 samples).
  • Spiked samples: 20 spiked samples at each of 5 concentrations (0, 37.5, 50, 62.5, 2000 ng/mL) resulting in a total of 100 spiked samples. Each lay user tested one spiked sample.
  • Data provenance: Performed at three intended user sites.
• Test Kit Reaction Time: 21 replicates of each of 7 concentrations (total 147 samples).
• Operator Intensity Reading: 25 replicates for each of 7 concentrations (total 175 samples).
• Specimen Collection Verification: 5 positive and 5 negative clinical samples per lay user (5 * 10 = 50 samples for the primary part of the study). Stool weight measurements were taken from these.

The overall provenance of the data appears to be a mix of "in-house" (likely in China, given the manufacturer's location) and "US POC sites" for reproducibility and method comparison studies. All studies appear to be prospective for the purpose of device validation.

3. Number of Experts and Qualifications:

• Adjudication and Ground Truth for Test Sets:
  • In the precision, stability, linearity, interference, specificity, and cut-off studies, the "ground truth" was established by the known concentrations of human hemoglobin or other substances spiked into Hb-free stool samples. This is an analytical ground truth, not requiring expert review of the results in the same way clinical data would.
  • For the Method Comparison Study, the predicate device (Orient Gene Biotech One Step Rapid FOB Test) served as the comparator, with its results being the "reference standard" against which the new device was compared. This implies the predicate device's results were considered the "ground truth" for comparison.
  • For the Lay-user study: "Professional testing" results were used as the ground truth for comparison. The document does not specify the qualifications of these "professionals," but it implies they are trained laboratory or clinical staff.
  • Specimen Collection Verification: A "professional operator" was involved in weighing samples. Qualifications are not specified.

4. Adjudication Method:

• There is no mention of an adjudication method (like 2+1 or 3+1 consensus) for establishing the ground truth of the test sets. The studies rely on:
  • Analytical ground truth: Spiked samples with known concentrations.
  • Comparative ground truth: Comparison against a legally marketed predicate device or "professional testing" results.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:

• No, a multi-reader multi-case (MRMC) comparative effectiveness study focusing on how much human readers improve with AI vs. without AI assistance was reported. This device is a rapid diagnostic test (FOBT) for the qualitative detection of human occult blood. It is not an AI-powered image analysis device, nor does it appear to involve human "readers" interpreting complex medical images in the way an MRMC study would typically evaluate. The "operators" or "lay users" in this context are performing the test and reading a simple positive/negative result, not interpreting complex data.
• The "Operator Intensity Reading" study involved multiple readers (five) but it was to assess consistency of subjective intensity grading, not comparative effectiveness with/without AI assistance.

6. Standalone Performance:

• Yes, extensive standalone performance was done. The entire "Analytical Performance" section (Precision/Reproducibility, Linearity, Stability, Interference, Specificity, Cut-off) details the algorithm's (device's) performance characteristics independently of human-in-the-loop clinical decision making, by testing samples with known analytical parameters.
• The "Method Comparison Studies" also describe the standalone performance of the device against a predicate device.
• The "Lay-user study" also tested the standalone performance of the device when used by lay users, comparing their results to professional results.

7. Type of Ground Truth Used:

• Primarily analytical ground truth (known concentrations of human hemoglobin or other substances in spiked stool samples) for most of the analytical performance studies (precision, stability, linearity, interference, specificity, cut-off).
• Comparative ground truth using a legally marketed predicate device (Orient Gene Biotech One Step Rapid FOB Test) for the method comparison study.
• Comparison to "professional testing" results for the lay-user study.

8. Sample Size for the Training Set:

• The document does not mention or specify a training set in the context of an algorithm or AI. This device is a lateral flow immunochromatographic assay, which is a chemical and biological test, not an AI/machine learning model that typically requires a large training dataset. The development and optimization of such a test would involve internal R&D experiments to determine optimal reagent concentrations, membrane properties, etc., but these are not referred to as a "training set" in the context of AI/ML.

9. How the Ground Truth for the Training Set was Established:

• As there is no mention of a training set for an AI/ML algorithm, this question is not applicable to the submitted document.

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Wondfo Amphetamine Urine Test AMP 500 Cup is an immunochromatographic assay for the qualitative determination of Amphetamine in human urine at a Cut-Off concentration of 500 ng/mL. This test is calibrated to d-Amphetamine (calibrator).

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive. For in vitro diagnostic use only. This test is intended for over-the-counter (OTC) consumer use as the first step in a twostep process to provide consumers with information concerning the presence of the above stated drugs or their metabolites in a urine sample. Information regarding confirmatory testing- the second step in the process, is provided in the package labeling.

Wondfo Amphetamine Urine Test AMP 500 DipCard is an immunochromatographic assay for the qualitative determination of Amphetamine in human urine at a Cut-Off concentration of 500 ng/mL. This test is calibrated to d-Amphetamine (calibrator).

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive. For in vitro diagnostic use only. This test is intended for over-the-counter (OTC) consumer use as the first step in a twostep process to provide consumers with information concerning the presence or absence of the above stated drugs or their metabolites in a urine sample. Information regarding confirmatory testing- the second step in the process, is provided in the package labeling.

Wondfo Cocaine Urine Test COC 150 Cup is an immunochromatographic assay for the qualitative determination of Benzoylecgonine in human urine at a Cut-Off concentration of 150 ng/mL. This test is callbrated to Benzoylecgonine (calibrator).

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive. For in vitro diagnostic use only. This test is intended for over-the-counter (OTC) consumer use as the first step in a twostep process to provide consumers with information concerning the presence or absence of the above stated drugs or their metabolites in a urine sample. Information regarding confirmatory testing- the second step in the process, is provided in the package labeling.

Wondfo Cocaine Urine Test COC 150 DipCard is an immunochromatographic assay for the qualitative determination of Benzoylecgonine in human urine at a Cut-Off concentration of 150 ng/mL. This test is callbrated to Benzoylecgonine (calibrator).

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive. For in vitro diagnostic use only. This test is intended for over-the-counter (OTC) consumer use as the first step in a twostep process to provide consumers with information concerning the presence of the above stated drugs or their metabolites in a urine sample. Information regarding confirmatory testing- the second step in the process, is provided in the package labeling.

Wondfo Methamphetamine Urine Test MET 500 Cup is an immunochromatographic assay for the qualitative determination of Methamphetamine in human urine at a Cut-Off concentration of 500 ng/mL. This test is calibrated to d-Methamphetamine (calibrator).

The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive. For in vitro diagnostic use only. This test is intended for over-the-counter (OTC) consumer use as the first step in a twostep process to provide consumers with information concerning the presence or absence of the above stated drugs or their metabolites in a urine sample. Information regarding confirmatory testing- the second step in the process, is provided in the package labeling.

Wondfo Amphetamine Urine Test MET 500 DipCard is an immunochromatographic assay for the qualitative determination of Methamphetamine in human urine at a Cut-Off concentration of 500 ng/mL. This test is calibrated to d-Methamphetamine (calibrator).

The test provides only preliminary test results. A more specific alternative chemical must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive. For in vitro diagnostic use only. This test is intended for over-the-counter (OTC) consumer use as the first step in a twostep process to provide consumers with information concerning the presence or absence of the above stated drugs or their metabolites in a urine sample. Information regarding confirmatory testing- the second step in the process, is provided in the package labeling.

WONDFO Urine Test devices are immunochromatographic assays for cocaine, amphetamine and Methamphetamine. Each assay test is a lateral flow, one step system for the qualitative detection of Benzoylecgonine, or D-amphetamine or D-methamphetamine (target analyte) in human urine. The product is a single-use in vitro diagnostic device, which comes in the form of: DipCards, or Cups. It contains a Test Device (in one of the two formats), a package insert and a urine cup. Each test device is sealed with a desiccant in an aluminum pouch.

The document provides information on the acceptance criteria and performance of the Wondfo Amphetamine/Cocaine/Methamphetamine Urine Tests.

Here's the breakdown:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state "acceptance criteria" in a table format with a direct comparison to performance against those criteria. Instead, it presents performance characteristics (precision, cut-off verification, interference, specificity, effects of specific gravity and pH, agreement with GC/MS, and lay-user performance) which implicitly define the device's acceptable performance. The performance demonstrated is the acceptance criteria met.

Implicit Acceptance Criteria and Reported Device Performance (Summary derived from the text):

The study demonstrates that the Wondfo Urine Test devices perform as expected for qualitative drug detection around specified cut-off levels, show appropriate specificity, are not significantly affected by common interfering substances or urine properties, and can be used accurately by lay-users. This collective performance data indicates that the devices meet the implied acceptance criteria for their intended use as preliminary, over-the-counter drug screening tests.

Study Details:

2. Sample Size and Data Provenance

• Test Set Sample Size:

  • Precision Studies: For each drug concentration, three lots of devices were tested, with two runs per day for 25 days. The number of individual tests per concentration point for each lot is not explicitly stated as a single total, but 50 measurements (e.g., 50-/0+ or 50+/0-) are reported for each concentration for each lot. This implies 50 tests per concentration per lot for each of "Lot 1, Lot 2, Lot 3". Given 9 concentration points per drug, that's 9 * 50 = 450 tests per lot, and 3 lots means 1350 tests per drug for each device format (Cup/DipCard).
  • Cut-off Verification: 150 samples were used in total, equally distributed across 5 concentrations (-50%, -25%, cut-off, +25%, +50%). Tested using three different lots of each device by three different operators. (This means 150 samples * 3 lots * 3 operators = 1350 individual test results reported for this section across all drugs and device formats).
  • Interference & Specificity Studies: Not explicitly stated as a total N, but substances were added to drug-free urine and target-drug urine (25% above cut-off) and tested using "three batches of each device for all formats."
  • Method Comparison (Agreement with GC/MS): 80 unaltered clinical samples (40 negative, 40 positive) were used for each drug (Amphetamine, Cocaine, Methamphetamine) for each device format (Cup/DipCard).
  • Lay-user Study: 280 lay persons for Amphetamine devices, 280 for Cocaine devices, and 280 for Methamphetamine devices. Each lay person tested one blind-labeled sample. For each drug, 7 distinct concentration levels with 20 samples per level were used. This means 7 * 20 = 140 samples were prepared for each drug per device format (e.g., AMP Cup), and these samples were then distributed to the 280 lay users (presumably 140 for the Cup and 140 for the DipCard, but this is not explicitly stated for all, though AMP and COC show 140 samples in total distributed across the 7 concentrations for both Cup and DipCard results tables).

• Data Provenance:

  • Country of Origin: Wondfo Biotech Co., Ltd. is located in Guangzhou, P.R. China (page 4). The studies were likely conducted internally or by associated labs.
  • Retrospective or Prospective: Not explicitly stated, but the "clinical samples" for the method comparison were "unaltered," which often implies prospectively collected real-world samples. The precision and cut-off studies involved "spiking drug in negative samples" which are laboratory-prepared. The lay-user study used prepared samples and was a controlled prospective study.

3. Number of Experts and Qualifications for Ground Truth

• Method Comparison (Agreement with GC/MS):

  • The ground truth was established by GC/MS (Gas Chromatography/Mass Spectrometry), which is the preferred confirmatory method for drug testing, considered the "gold standard."
  • No human "experts" were listed as establishing ground truth for the test set; the GC/MS analytical results served as the objective gold standard.
  • Three "laboratory assistants" were involved in running the Wondfo devices, not in establishing the ground truth. Their qualifications are not provided.

• Precision, Cut-off, Interference, Specificity, Specific Gravity/pH: The ground truth for these studies was established by the precise preparation of samples with known drug concentrations (confirmed by GC/MS where relevant) and the analytical methods used to prepare and characterize the samples.

• Lay-user Study: The ground truth for the lay-user study was established by GC/MS for the prepared urine samples.

4. Adjudication Method for the Test Set

• Method Comparison: No formal "adjudication method" among human readers is described for the test sets. The Wondfo device results (read by the laboratory assistants/viewers) were directly compared to the GC/MS ground truth. Discordant results are noted individually for each viewer against the GC/MS result.
• Precision/Cut-off: Not applicable, as results were based on predefined expectations for concentrations.
• Lay-user Study: Not applicable, as each lay person read their assigned sample independently against the GC/MS-confirmed concentration.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

• No MRMC comparative effectiveness study was explicitly performed or reported in this document to assess how much human readers improve with AI (or rather, with the device) versus without assistance.
• The studies were designed to evaluate the performance of the device itself and the ability of lay users to correctly interpret device results compared to a gold standard (GC/MS).
• The "Method Comparison" section involved three "viewers" (laboratory assistants) independently reading the device results and comparing them to GC/MS. This is a multi-reader study, but it's evaluating the device's accuracy when read by trained personnel, not necessarily the improvement of those readers.
• The "Lay-user study" is also a multi-reader study (280 lay persons), but it's assessing the device's ease of use and accuracy in untrained hands, not an improvement over unassisted human performance.

6. Standalone Performance Study

• Yes, a standalone performance study was done. The core of the document describes the standalone performance of the Wondfo Urine Test device itself.
  • The "Precision," "Cut-off," "Interference," and "Specificity" sections evaluate the analytical performance of the device in a laboratory setting when operated by laboratory personnel, without explicit human-in-the-loop decision-making beyond visual interpretation of a test line.
  • The "Method Comparison" study explicitly compares the device's qualitative results (interpreted visually by laboratory assistants) against the GC/MS gold standard. This is a direct measure of the device's standalone performance in a simulated clinical context.

7. Type of Ground Truth Used

• The primary ground truth used for all performance studies (precision, cut-off, interference, specificity, method comparison, lay-user study) for drug concentrations was GC/MS (Gas Chromatography/Mass Spectrometry). GC/MS is a highly accurate analytical chemistry technique considered the definitive "confirmatory method" for drug identification and quantification in urine.
• For the lay-user study, the ground truth for ease of use was collected via user surveys.

8. Sample Size for the Training Set

• Not Applicable. This device is an immunochromatographic assay (lateral flow immunoassay), not a machine learning or AI-based device that typically requires a "training set" in the computational sense. The device's performance is based on its chemical and biological design, not a trained algorithm.

9. How the Ground Truth for the Training Set Was Established

• Not Applicable, as there is no "training set" for this type of device. The ground truth for the validation/test samples was established via GC/MS.

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Wondfo Propoxyphene Urine Test is an immunochromatographic assay for the qualitative determination of d-Propoxyphene in human urine at a cutoff concentration of 300 ng/mL. The test is available in a dip card format and a test cup format. It is intended for prescription use and over the counter use. The test provides only preliminary test results. A more specific alternative chemical must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. The test will yield preliminary positive results when prescription drug d-Propoxyphene is ingested, even at or above therapentic doses. There is no uniformly recognized cutoff concentration for d-Propoxyphene. It is not intended to distinguish between prescription use or abuse of this drug. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive.

The Wondfo Propoxyphene Urine Test uses immunochromatographic assays for d-Propoxyphene. The test is a lateral flow system for the qualitative detection of d-Propoxyphene in human urine. The test is the first step in a two-step process. The second step is to send the sample for laboratory testing if preliminary positive results are obtained.

Here's a breakdown of the acceptance criteria and study information for the Wondfo Propoxyphene Urine Test devices, as extracted from the provided document:

1. Table of Acceptance Criteria and Reported Device Performance

The document primarily focuses on a "Lay-user study" for establishing performance in the context of an OTC claim addition. The acceptance criteria for this study are implied by the desired percentage of correct results for various d-Propoxyphene concentrations relative to the 300 ng/mL cutoff. While explicit numerical acceptance criteria (e.g., "must achieve X% accuracy") are not stated, the study demonstrates desired performance.

2. Sample Sizes Used for the Test Set and Data Provenance

• Sample Size for Test Set:
  • Lay-user study: 280 lay persons in total, with 140 testing the cup format and 140 testing the dip card format. Each lay person tested one blind-labeled sample.
  • For each concentration level represented in the table above, there were 20 samples for the cup format and 20 samples for the dip card format.
• Data Provenance: The document does not explicitly state the country of origin for the data or if it was retrospective or prospective. Given that the submitter is Guangzhou Wondfo Biotech Co., Ltd. from China, and the study was performed "at three intended user sites," it's likely the samples and study were conducted in China, and it appears to be a prospective study designed for this submission.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

• Number of Experts: Not applicable in the context of expert review for ground truth in this lay-user study.
• Qualifications of Experts: Not applicable.

4. Adjudication Method for the Test Set

• Adjudication Method: Not applicable. The "ground truth" was established independently by GC/MS and then compared directly to the lay user's interpretation.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done

• MRMC Study: No, an MRMC comparative effectiveness study was not explicitly mentioned or performed in the provided text. The study described is a lay-user study comparing the device's output (as interpreted by lay users) against a gold standard (GC/MS).

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was Done

• Standalone Performance: The Wondfo Propoxyphene Urine Test is an immunochromatographic assay, which is a rapid diagnostic test interpreted by a human. Therefore, the concept of a "standalone algorithm" doesn't directly apply in the same way it would for a digital imaging AI device. The lay user study is a test of human-in-the-loop performance, where the human interprets the result of the assay. The results for the cup and dip card formats are reflective of the final human-interpreted output.

7. The Type of Ground Truth Used

• Type of Ground Truth: The ground truth for the test samples was established by Gas Chromatography/Mass Spectrometry (GC/MS). The document states: "The concentrations of the samples were confirmed by GC/MS."

8. The Sample Size for the Training Set

• Sample Size for Training Set: The document does not describe a distinct "training set" in the context of machine learning. The device is an immunochromatographic assay, not an AI/ML algorithm that requires training data. Its "training" would involve internal development and optimization by the manufacturer using various chemical and biological samples, but this is not detailed in the provided regulatory document.

9. How the Ground Truth for the Training Set Was Established

• Ground Truth for Training Set: Not applicable as there is no described AI/ML training set. The assay's performance relies on the specific antibodies and reagents designed to detect propoxyphene, and its development would involve internal validation by the manufacturer using known standards and clinical samples, confirmed typically by methods like GC/MS.

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Wondfo One Step HCG Urine Pregnancy Test Strip is a rapid chromatographic immunoassay for the qualitative detection of human chorionic gonadotropin (bCG) in urine, as an aid in early detection of pregnancy, in some cases as early as five (5) days before the expected period, i.e., as early as six (6) days before the day of the missed period. Important note regarding negative results: Some pregnant women will not be able to detect hCG in their urine 5 days before the expected period. If you test negative before your missed period, but think you may still be pregnant, you should test again a few days after your missed period. Important note regarding positive results: Because this test detects low levels of hCG, it is possible that this test may give positive results even if you are not pregnant. If you test positive, but think you may not be pregnant, you should check with your doctor. All results should be confirmed by your healthcare provider, especially when making decisions about future medical care. This product is intended for both prescription use and over-the-counter use.

Wondfo One Step HCG Urine Pregnancy Test Cassette is a rapid chromatographic immunoassay for the qualitative detection of human chorionic gonadotropin (hCG) in urine, as an aid in early detection of pregnancy, in some cases as early as five (5) days before the expected period, i.e., as early as six (6) days before the day of the missed period. Important note regarding negative results: Some pregnant women will not be able to detect hCG in their urine 5 days before the expected period. If you test negative before your missed period, but think you may still be pregnant, you should test again a few days after your missed period. Important note regarding positive results: Because this test detects low levels of hCG, it is possible that this test may give positive results even if you are not pregnant. If you test positive, but think you may not be pregnant, you should check with your doctor. All results should be confirmed by your healthcare provider, especially when making decisions about future medical care. This product is intended for both prescription use and over-the-counter use.

Wondfo One Step HCG Urine Pregnancy Test Midstream is a rapid chromatographic immunoassay for the qualitative detection of human chorionic gonadotropin (hCG) in urine, as an aid in early detection of pregnancy, in some cases as early as five (5) days before the expected period, i.e., as early as six (6) days before the day of the missed period. Important note regarding negative results: Some pregnant women will not be able to detect hCG in their urine 5 days before the expected period. If you test negative before your missed period, but think you may still be pregnant, you should test again a few days after your missed period. Important note regarding positive results: Because this test detects low levels of hCG, it is possible that this test may give positive results even if you are not pregnant. If you test positive, but think you may not be pregnant, you should check with your doctor. All results should be confirmed by your healthcare provider, especially when making decisions about future medical care. This product is intended for over-the-counter use.

Each of the devices (strip, cassette, and midstream) contains a pouch with the test and instructions. The cassette and midstream nitrocellulose test strips are contained in plastic housing. The cassette test also contains a dropper. The strips of each device contain mouse monoclonal anti-β-hCG antibody colloidal gold conjugate pre-dried on the pad, mouse monoclonal anti-u-hCG antibody (on the Test Line) and goat anti mouse IgG polyclonal antibody (on the Control Line).

Here's a breakdown of the acceptance criteria and study details for the Wondfo One Step HCG Urine Pregnancy Test, as extracted from the provided document:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state "acceptance criteria" in a tabulated format with pass/fail marks. However, it presents the performance characteristics measured and the results obtained for the device. Based on the information provided, we can infer the performance criteria and the device's reported performance:

• 7.5 mIU/mL: ~28-30% positive across formats and lots.
• 8 mIU/mL: ~50-51.7% positive across formats and lots.
• 9 mIU/mL: ~88.3-90% positive across formats and lots.
• 10 mIU/mL and above: 100% positive across formats and lots. |
  | Stability: Maintain performance over time. | Stable at 4-30°C for 24 months (based on accelerated stability at 50°C and real-time stability at 4°C and 30°C). |
  | Specificity and Cross-Reactivity: No interference from high hCG concentrations (no hook effect), different hCG fragments (B-core), or other glycoprotein hormones (LH, FSH, TSH). | High Dose Effect: No hook effect observed at hCG concentrations ranging from 6,250 to 200,000 mIU/mL.
  Effects of hCG ß-core fragment: No interference observed for urine samples with 0 mIU/mL hCG and 10 mIU/mL hCG (except false negative at 500,000 pmol/L of ß-core fragment hCG, which is a very high concentration).
  Effects of glycoprotein LH, FSH and TSH: No interference observed at LH concentrations up to 500 IU/mL, FSH concentrations up to 1000 mIU/mL, and TSH concentrations up to 1000 µIU/mL. |
  | Interfering Substances: No interference from various common substances. | No interference observed for all 20 tested compounds (Acetaminophen, Acetylsalicylic acid, Ascorbic acid, Atropine, Caffeine, Gentisic acid, Glucose, Hemoglobin, Tetracycline, Ampicillin, Albumin, B-hydroxybutyrate, Ephedrine, Phenylpropanolamine, Phenothiazine, EDTA, Salicyclic Acid, Benzoylecgonine, Cannabinol, Codeine, Ethanol, Bilirubin, Atropine, Pregnanediol, Thiophene, Ketone) at stated concentrations, for both 0, 10, and 100 mIU/mL hCG samples. |
  | Effect of Urine Specific Gravity and Urine pH: Consistent performance across varying urine properties. | No interference from pH ranging from 4 to 9.
  No interference from specific gravity ranging from 1.000 to 1.035. |
  | Precision: Consistent results across multiple replicates, operators, and lots. | Consistent results across 10 replicates for 5 consecutive days by three different operators at 3 POC sites, using 3 different lots for each format, for hCG concentrations ranging from 0 to 50 mIU/mL. E.g., for 10 mIU/mL, all 50 replicates were positive across all 3 lots for all formats. For 0, 2.5, 5 mIU/mL, all 50 replicates were negative across all 3 lots for all formats. The detection rates for 7.5 mIU/mL and 8 mIU/mL show expected variability around the cut-off. |
  | Method Comparison with Predicate Device: High agreement with a legally marketed predicate device. | 100% agreement for both positive and negative samples when compared to the FIRST RESPONSE™ Early Result Pregnancy Test (K123436) for all three device formats (Strip, Cassette, Midstream). |
  | Lay Person Study: Ease of use and accuracy when used by intended lay users. | Overall Agreement with Professional:
• Strip: 100% agreement (49+/51- vs 49+/51-).
• Cassette: 99% agreement (48+/51- vs 48+/52-), with 1 false positive by lay person.
• Midstream: 100% agreement (49+/51- vs 49+/51-).
  Correctness for Spiked Samples (5mIU/ml, 10mIU/ml):
• Strip: 99% for 5mIU/ml (1+/99-), 100% for 10mIU/ml (100+/0-). (Note: The table on page 13 for strips and 5 mIU/mL seems to have a typo, showing 1 positive for 5mIU/mL. The overall result for lay person vs professional for strips is 100% agreement, which contradicts the 1 positive result for 5mIU/mL in the next table. Assuming the professional comparison is the primary indicator of overall accuracy vs ground truth).
• Cassette: 100% for 5mIU/ml (0+/100-), 100% for 10mIU/ml (100+/0-).
• Midstream: 100% for 5mIU/ml (0+/100-), 99% for 10mIU/ml (99+/1-).
  Consistency for Spiked Samples (7.5mIU/mL, 8mIU/mL):
• Strip: 96% and 97%.
• Cassette: 96% and 96%.
• Midstream: 96% and 97%.
  Ease of Use: All lay users indicated instructions were easily followed. Flesch-Kincaid reading Grade Level of 7 for package inserts. |
  | False Positive Rate: Low rate of positive results in non-pregnant individuals. | Strip: 0.3% false positive results (1 false positive out of 300 non-pregnant females, from a peri-menopausal woman confirmed non-pregnant via ultrasound).
  Cassette: 0.3% false positive results (1 false positive out of 300 non-pregnant females, from a peri-menopausal woman confirmed non-pregnant via ultrasound).
  Midstream: 0% false positive results (0 out of 300 non-pregnant females). |
  | Early Pregnancy Detection: Ability to detect pregnancy early relative to the Expected Menstrual Period (EMP). | Detects:
• 68% positive hCG five days before EMP.
• 100% positive hCG on the day of EMP.
• Performance consistent across device formats. |
  | Substantial Equivalence: Overall performance comparable to the predicate device. | Concluded to be substantially equivalent to the predicate device (Church & Dwight Co., Inc. FIRST RESPONSE™ Early Result Pregnancy Test). |

2. Sample Size Used for the Test Set and Data Provenance

• Analytical Performance (Sensitivity/Cut-Off, Interference, Precision):
  • Sensitivity/Cut-Off: 20 replicates per hCG concentration level per lot (3 lots), tested by 12 operators. This means 60 tests per hCG level per format (e.g., for Strip format: 60 tests for 0mIU/ml, 60 for 5mIU/ml, etc.). The study used Urine standards containing intact hCG calibrated against WHO 4th IS for hCG. The provenance is not explicitly stated but is implied to be laboratory-prepared standards.
  • Specificity & Cross-reactivity: Samples (negative urine and 10 mIU/mL hCG) spiked with specified interfering substances. Each spiked sample was tested by 3 different lots and 3 different operators. The exact number of replicates per sample/condition is not explicitly stated, but for each interfering substance, a series of tests were done to ensure no interference.
  • Precision: 10 replicates per day for 5 consecutive days using 3 different lots for each format. This means 50 tests per hCG concentration per lot per format (e.g., for Strip format, 50 tests for 0mIU/ml, 50 for 2.5mIU/ml, up to 50 for 50mIU/ml, for each of the 3 lots). Tests were performed by 9 POC operators (3 for each format). The ground truth was negative human urine samples spiked with varying hCG concentrations (commercially available and traceable to 4th WHO international standard). Provenance is likely laboratory-prepared.
• Method Comparison with Predicate Device:
  • Sample Size: 100 urine samples for each format (total 300 samples).
  • Provenance: Collected from 100 women (about half pregnant, early stage at less than 5 weeks). Samples randomly collected at various times throughout the day. Ages ranged from 20 to 45 years. The provenance is clinical/human samples, seemingly prospective (collected for this study given the blind labeling and specific testing procedure). Country of origin is not specified.
• Lay Person Study:
  • Sample Size: 100 lay persons for the strip devices, 100 for the cassette devices, and 100 for the midstream devices (total 300 lay persons).
  • Provenance: For samples with known hCG concentrations, urine samples were prepared at 5mIU/ml, 8.0mIU/ml, 8.0mIU/ml hCG by spiking hCG into negative pooled urine specimens (laboratory-prepared). Additionally, each participant tested "her own urine sample" (clinical/human, self-collected). Provenance for lay users is diverse educational and professional backgrounds, aged 21 to >50 years, likely within the location of the study (not specified).
• False Positive Rate Study:
  • Sample Size: 300 non-pregnant females for strip, 300 for cassette, and 300 for midstream (total 900 non-pregnant female tests).
  • Provenance: Non-pregnant females who tested "their own urine samples" (clinical/human, self-collected). Provenance likely within the location of the study (not specified).
• Early Pregnancy Test Study:
  • Sample Size: 585 urine samples from 65 characterized cycle segments of conceptive cycles were collected from 65 pregnant women.
  • Provenance: Clinical/human samples from pregnant women.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

• Analytical Performance:
  • Sensitivity/Cut-Off: 12 operators tested each standard. Qualifications not specified, but likely laboratory technicians given the nature of the testing.
  • Specificity & Cross-reactivity: 3 different operators. Qualifications not specified, but likely laboratory technicians.
  • Precision: 9 Point-of-Care (POC) operators (3 different operators for each of 3 formats). Qualifications not specified, but suggests healthcare professionals.
• Method Comparison with Predicate Device:
  • Ground Truth: The "predicate device" serves as the reference standard.
  • Testing Personnel: 9 POC operators (three different health professionals at each of the 3 POC sites). Qualifications of "health professionals" not specified but implies skilled personnel.
• Lay Person Study:
  • Ground Truth: Professional testing of the same samples.
  • Testing Personnel: "Professional" testing results are compared to lay person results. The qualifications of these professionals are not explicitly stated, but it is implied they are trained individuals capable of accurately interpreting the test results.
• False Positive Rate Study:
  • Ground Truth: Derived from professional testing and, in some cases, ultrasound scan confirmation for the false positive results.
  • Testing Personnel: The results were from the non-pregnant females themselves, but the ground truth was also established by professional testing and, for the identified false positives, confirmed by ultrasound.
• Early Pregnancy Test Study:
  • Ground Truth: "Characterized cycle segments of conceptive cycles" from pregnant women indicate clinical diagnosis of pregnancy (likely through follow-up serum hCG, ultrasound, or confirmed delivery/outcome).
  • Testing Personnel: Tests were done by an unspecified number of individuals using all three formats. Implicitly, clinical professionals would have characterized the cycle segments.

4. Adjudication Method for the Test Set

The document does not explicitly describe a formal adjudication (e.g., 2+1, 3+1) method for conflicting interpretations of test results within the studies. Observations:

• Analytical Performance (Sensitivity/Cut-Off, Interference, Precision): For the sensitivity/cut-off and precision studies, results are reported as aggregates from multiple tests by multiple operators. It appears individual operator results were combined (e.g., 10-/10+ implies 10 negative, 10 positive results out of 20 by various operators). There's no mention of a consensus process for discrepant results at the individual reading level.
• Method Comparison and Lay Person Studies: These studies compare the device results to either a predicate device or professional results. The "Professional" results are presented as a single ground truth, implying any potential disagreements among professionals for the ground truth were already resolved or not present.
• False Positive Rate Study: For the two cases of false positives, an ultrasound scan was used for confirmation, which serves as a higher-level adjudication for those specific ambiguous cases.

5. If a Multi Reader Multi Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance

An MRMC comparative effectiveness study was not performed in the context of AI assistance. This document describes a medical device (pregnancy test strips/cassettes/midstream) that is a rapid chromatographic immunoassay, not an AI-powered diagnostic tool. Therefore, the concept of "human readers improve with AI vs without AI assistance" is not applicable here.

6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done

This is not applicable, as the device is a manual, qualitative immunoassay. There is no algorithm or AI component. The user (human-in-the-loop) visually interprets the results.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)

The type of ground truth varied by study:

• Analytical Performance:
  • Sensitivity/Cut-Off, Specificity, Interfering Substances, Precision, Urine Properties: Laboratory-prepared hCG standards (calibrated against WHO 4th IS for hCG) in negative urine pools, or negative urine samples spiked with known substances. This represents a highly controlled and quantitative ground truth.
• Method Comparison with Predicate Device:
  • The predicate device (FIRST RESPONSE™ Early Result Pregnancy Test) served as the comparative ground truth.
• Lay Person Study:
  • Professional testing results of the same samples. For samples with known hCG concentrations, the prepared hCG concentrations served as ground truth.
• False Positive Rate Study:
  • Confirmed non-pregnancy status (e.g., patient history, and in specific false positive cases, confirmed by ultrasound scan).
• Early Pregnancy Test Study:
  • Characterized conceptive cycles from pregnant women. This implies clinical confirmation of pregnancy based on biological outcomes (i.e., actual pregnancy).

8. The Sample Size for the Training Set

This document describes performance studies for an existing medical device, not the development or training of an AI algorithm. Therefore, there is no "training set" in the context of machine learning. The studies described are validation and verification studies for the device's performance.

9. How the Ground Truth for the Training Set Was Established

As there is no training set for an AI algorithm, this question is not applicable.

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The Wondfo CR3 Keyless Split Sample Cup is a competitive binding, lateral flow immunochromatographic assay for qualitative and simultaneous detection of Amphetamine, Secobarbital, Oxazepam, Cocaine, Cannabinoids, Methamphetamine, Methylenedioxymethamphetamine, Morphine, Oxycodone, Buprenorphine, Methadone and Notriptyline in human urine at the cutoff concentrations of:

Configuration of the Wondfo CR3 Keyless Split Sample Cup can consist of any combination of the above listed drug analytes.

The test provides only preliminary test results. A more specific alternative chemical must be used in order to obtain a confirmed analytical result. GC/MS or LC/MS is the preferred confirmatory method.

The test will yield preliminary positive results when prescription drugs Buprenorphine. Oxazepam, Oxycodone and Secobarbital are ingested, even at or above therapeutic doses. It is not intended to distinguish between prescription use or abuse of these drugs.

Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive.

The Wondfo CR3 Keyless Split Sample Cup uses immunochromatographic assays for qualitative and simultaneous detection of Amphetamine, Secobarbital, Oxazepam, Cocaine, Cannabinoids, Methamphetamine, Methylenedioxymethamphetamine, Morphine, Phencyclidine, Oxycodone Buprenorphine, Methadone and Notriptyline in human urine samples. The test is a lateral flow, competitive binding system. The test is the first step in a two-step process. The second step is to send the sample for laboratory testing if preliminary positive results are obtained.

Here's a breakdown of the acceptance criteria and study information for the Wondfo CR3 Keyless Split Sample Cup, based on the provided document:

1. Table of Acceptance Criteria and Reported Device Performance:

The document describes the device as a qualitative test, meaning it determines the presence or absence of a substance, not its exact quantity. The performance is assessed against specific cut-off levels for each drug. The provided text, however, focuses on analytical performance being established in previous 510(k) submissions for individual drug tests and then verifying functionality in a multi-drug cup configuration. It explicitly states: "The test strips of the candidate device are the same as those cleared with the predicate devices. Drug cutoffs of the candidate device are also identical to the predicate devices. Analytical performance was established for each device in the submissions as stated below."

Therefore, the acceptance criteria are implicitly tied to the performance demonstrated in those predicate device submissions. The table below lists the drugs and their cut-off levels, which are the primary performance metric. The "Reported Device Performance" here refers to the device's ability to qualitatively detect these drugs at or above these cut-off levels, which was verified to be consistent with the predicate.

2. Sample Size Used for the Test Set and Data Provenance:

• Sample Size for Test Set: The document does not explicitly state a specific sample size for the current 510(k) submission's test set. It refers to "verification studies" for the multi-drug cup modification, including interference studies and a lay-user study. The analytical performance was established in previous 510(k) submissions (e.g., K141532 for Amphetamine). To get the detailed sample sizes for the analytical performance, one would need to refer to those predicate submissions.
• Data Provenance: The document does not specify the country of origin for the data used in the "verification studies" or the previous analytical performance studies. It mentions the submitter is Guangzhou Wondfo Biotech Co., Ltd., from P.R. China, but this doesn't directly indicate where the clinical or analytical samples were sourced. The studies appear to be retrospective in the sense that the individual drug test performance was already established and used, but the verification of the multi-drug cup format would likely involve prospective testing with new samples in the modified device.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications of Experts:

The document does not provide this information. Given that this is an in vitro diagnostic device for drug detection in urine, the "ground truth" for analytical performance is typically established by reference laboratory methods (e.g., GC/MS or LC/MS), not human expert consensus on subjective interpretations. For the lay-user study, if included, experts might be involved in evaluating user comprehension and performance, but this is not detailed.

4. Adjudication Method for the Test Set:

Not applicable. For a qualitative drug test where ground truth is established by chemical analysis (GC/MS or LC/MS), there is no need for expert adjudication in the traditional sense, as the reference method provides a definitive result.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done:

No, an MRMC comparative effectiveness study was not done. This type of study is typically associated with image-based diagnostics where multiple readers interpret cases and their performance is compared with and without AI assistance. The Wondfo CR3 Keyless Split Sample Cup is a rapid, qualitative immunoassay for drug detection, where the result is typically read visually as "positive" or "negative" based on line appearance, not complex interpretation.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done:

Yes, the analytical performance studies (both for the predicate devices and the verification studies for the new cup format) represent standalone performance. The device itself produces a visual result, and its accuracy is tested against a chemical comparator without a human actively "interpreting" or making a diagnostic decision beyond reading the visual output. The device's performance is independent of human interpretation variability once the result lines are formed.

7. The Type of Ground Truth Used:

The primary type of ground truth used would be chemical analysis, specifically GC/MS or LC/MS (Gas Chromatography/Mass Spectrometry or Liquid Chromatography/Mass Spectrometry). The document explicitly states: "A more specific alternative chemical must be used in order to obtain a confirmed analytical result. GC/MS or LC/MS is the preferred confirmatory method." This indicates that these methods serve as the gold standard for confirming drug presence and concentration.

8. The Sample Size for the Training Set:

The document does not explicitly state a sample size for the training set. For in vitro diagnostic devices like this, antibody and assay development would involve extensive experimentation and optimization (which can be considered analogous to "training") using a variety of standards and spiked samples, but a formal "training set" in the machine learning sense is not typically described in these submissions. The analytical performance data from the predicate devices could be considered the "learned" performance that the new device aims to replicate in its modified format.

9. How the Ground Truth for the Training Set Was Established:

As above, the concept of a "training set" in the machine learning context isn't directly applicable here. For the development and optimization of the assays (the "training" equivalent), ground truth would have been established using known concentrations of drug analytes and metabolites in synthetic or drug-free human urine samples, confirmed through highly accurate analytical methods like GC/MS or LC/MS. This allows for precise calibration and characterization of the assay's sensitivity and specificity.

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