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The Acucy Influenza A&B Test is a rapid chromatographic immunoassay for the qualitative detection and differentiation of influenza A and B viral nucleoprotein antigens directly from anterior nasal and nasopharyngeal swabs from patients with signs and symptoms of respiratory infection. The test is intended for use with the Acucy or Acucy 2 Reader as an aid in the diagnosis of influenza A and B viral infections. The test is not intended for the detection of influenza C viruses. Negative test results are presumptive and should be confirmed by viral culture or an FDA-cleared influenza A and B molecular assay. Negative test results do not preclude influenza viral infection and should not be used as the sole basis for treatment or other patient management decisions.

Performance characteristics for influenza A were established during the 2017-2018 influenza season when influenza A/H3N2 and A/H1N1pdm09 were the predominant influenza A viruses in circulation. When other influenza A viruses are emerging, performance characteristics may vary.

If an infection with a novel influenza A virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.

The Acucy Influenza A&B Test allows for the differential detection of influenza A and influenza B antigens, when used with the Acucy 2 Reader. The patient sample is placed in the Extraction Buffer vial, during which time the virus particles in the sample are disrupted, exposing internal viral nucleoproteins. After disruption, the sample is dispensed into the Test Cassette sample well. From the sample well, the sample migrates along the membrane surface. If influenza A or B viral antigens are present, they will form a complex with mouse monoclonal antibodies to influenza A and/or B nucleoproteins conjugated to colloidal gold. The complex will then be bound by a rat anti-influenza A and/or mouse anti-influenza B antibody coated on the nitrocellulose membrane.

Depending upon the operator's choice, the Test Cassette is either placed inside the Acucy 2 Reader for automatically timed development mode (WALK AWAY Mode) or placed on the counter or bench top for a manually timed development and then placed into Acucy 2 Reader to be scanned (READ NOW Mode).

The Acucy 2 Reader will scan the Test Cassette and measure the absorbance intensity by processing the results using method-specific algorithms. The Acucy 2 Reader will display the test results POS (+), NEG (-), or INVALID on the screen. The results can also be automatically printed on the optional Printer if this option is selected.

Here's a breakdown of the acceptance criteria and the studies performed for the Acucy Influenza A&B Test with the Acucy 2 System, based on the provided FDA 510(k) clearance letter:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state "acceptance criteria" for each study, but rather presents the results and the implication that these results demonstrate the equivalence and performance of the device. For the purpose of this table, I will infer the implicit acceptance criteria from the expected outcomes and the conclusion that the device is "substantially equivalent."

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

• Precision Study (Repeatability & Instrument-to-Instrument): These studies primarily used contrived samples (prepared in the laboratory by spiking virus into clinical matrix) rather than naturally occurring patient samples.
  • Repeatability: 80 replicates per panel member (Flu A MP, LP, HN; Flu B MP, LP, HN; Negative) for both Acucy and Acucy 2. Total of 7 x 80 = 560 tests per device (Acucy and Acucy 2).
  • Instrument-to-Instrument Precision: 75 replicates per panel member (7 panel members). Total of 7 x 75 = 525 tests per device.
  • Data Provenance: Laboratory-generated, in vitro data. The origin of the clinical matrix used for preparing contrived samples is described as "nasal swab samples... collected from healthy donors and confirmed Flu negative by PCR" for LoD studies, likely similar for precision studies. No specific country of origin is mentioned, but typically for FDA submissions, this data is generated in the US or under comparable quality systems. It is retrospective in the sense that the samples were prepared and tested.
• Test Mode Equivalency: 20 replicates each of contrived positive Flu A, 20 replicates of contrived positive Flu B, and 20 Flu A and Flu B negative samples. Total of 60 tests (3 x 20 replicates). Data provenance is laboratory-generated/contrived.
• Limit of Detection (LoD):
  • Range Finding: 5 replicates per concentration for multiple strains and dilutions (as shown in Table 5).
  • Confirmation Testing: 20 replicates per concentration for established LoD.
  • Data Provenance: Contrived samples using pooled negative clinical matrix from healthy donors (confirmed Flu negative by PCR). Laboratory-generated, in vitro data.
• Analytical Cutoff Study: 60 replicates of a blank sample per lot. Total of 2 lots, so 120 tests. Data provenance is laboratory-generated/contrived.
• Cross-Contamination Study: 30 high titer Flu A positive, 30 high titer Flu B positive, and 60 negative samples. Total of 120 tests. Data provenance is laboratory-generated/contrived.
• Method Comparison (Acucy Reader vs. Acucy 2 Reader):
  • Test Set: 30 PCR-confirmed Flu A positive clinical samples, 30 PCR-confirmed Flu B positive clinical samples, and 30 Flu A and Flu B negative clinical samples.
  • Total N for Flu A analysis: 30 Flu A positive + (30 Flu B positive + 30 double negative) = 90 samples.
  • Total N for Flu B analysis: 30 Flu B positive + (30 Flu A positive + 30 double negative) = 90 samples.
  • Data Provenance: Clinical samples (retrospective, given they are PCR-confirmed and a specific count is provided). No country of origin is explicitly stated.
• CLIA Waiver Studies (Flex Studies): 5 replicates for each flex condition (Negative, Low Positive Flu A, Low Positive Flu B). Number of flex conditions is not explicitly totaled but over 10 types are listed. Data provenance is laboratory-generated/contrived.
• Reproducibility Studies (External Multi-Site):
  • Acucy System: Panel of 7 samples (Flu A HN, LP, MP; Flu B HN, LP, MP; Negative). Two operators per site, 3 sites, over 5 non-consecutive days. This means 30 replicates per sample type per site (2 operators * 5 days * 3 replicates assumed for LP/HN based on typical studies, though not explicitly stated as count of 30, but total is 90). So, 90 replicates per sample type across all sites (3 sites * 30 replicates). Overall N for Flu A or Flu B: 4 sample types * 90 replicates = 360 tests.
  • Acucy 2 System: Same design as above. 90 replicates per sample type (Flu A HN, LP, MP; Flu B HN, LP, MP; Influenza A & B Negative), across 3 sites. Overall N for Flu A or Flu B: 4 sample types * 90 replicates = 360 tests.
  • Data Provenance: Contrived samples (negative, high negative, low positive, moderate positive) with coded, randomized, and masked conditions. Tested at 3 "point-of-care (POC) sites" for Acucy and 3 "laboratory sites" for Acucy 2. This suggests real-world testing environments, but with contrived samples.

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

For most analytical studies (precision, LoD, analytical cutoff, cross-contamination, flex studies), the ground truth is established by known concentrations of spiked viral material in a controlled laboratory setting. Therefore, dedicated "experts" for ground truth adjudication in these cases are not applicable in the same way as for clinical studies.

For the Method Comparison study (Acucy Reader vs. Acucy 2 Reader), the ground truth for the clinical samples was established by PCR confirmation. The document does not specify the number of experts or their qualifications for interpreting these PCR results, but PCR results are generally considered a high standard for viral detection.

For the Reproducibility Studies, the ground truth for the test panel was established by the known composition of the contrived samples (e.g., negative, high negative, low positive, moderate positive).

4. Adjudication Method for the Test Set

• Analytical Studies (Precision, LoD, Analytical Cutoff, Cross-Contamination, Flex Studies, Reproducibility): Adjudication is inherently by known input concentration or known sample composition. There isn't an "adjudication method" in the sense of multiple human reviewers; rather, it's a comparison to the predefined true state of the contrived sample.
• Method Comparison Study: The ground truth for clinical samples was established by PCR confirmed results. The device's results were compared against these PCR results. There is no mention of human expert adjudication (e.g., 2+1 or 3+1 consensus) for the PCR results themselves or for resolving discrepancies between the device and PCR.

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

There is no MRMC comparative effectiveness study described in this document.

• The device is an automated reader for a rapid chromatographic immunoassay. It does not appear to involve human interpretation of images or complex data that would typically benefit from AI assistance in the way an MRMC study evaluates.
• The study focuses on the performance of the device (Acucy 2 System) only compared to a predicate device (Acucy System) and against laboratory-defined ground truths. There's no "human-in-the-loop" aspect being evaluated in terms of improved human reader performance with AI.

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

Yes, the studies presented are primarily standalone performance studies for the Acucy 2 System. The device (Acucy 2 Reader) automatically scans the test cassette and processes results using "method-specific algorithms" (Page 6). The output is "POS (+), NEG (-), or INVALID" displayed on the screen. The entire workflow described (from sample application to reader result) represents the standalone performance of the device and its embedded algorithms.

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

The ground truth used varied depending on the study:

• Analytical Studies (Precision, LoD, Analytical Cutoff, Cross-Contamination, Flex Studies, Reproducibility): Ground truth was based on known concentrations of spiked viral material in contrived samples. For negative controls, it was the absence of the target virus.
• Method Comparison Study: Ground truth for clinical samples was established by PCR confirmation.

8. The sample size for the training set

The document does not explicitly describe a training set or its sample size. The reported studies are primarily verification and validation studies to demonstrate performance and equivalence of the Acucy 2 System compared to the predicate Acucy System. For medical devices, especially immunoassay readers, algorithms are often developed and locked down before these validation studies are performed. If machine learning or AI was used in the algorithm development, the training data would precede these clearance studies and is typically not fully disclosed in a 510(k) summary unless directly relevant to a specific "software change" or unique characteristic being validated.

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

As no training set is explicitly mentioned, the method for establishing its ground truth is also not specified in this document. If algorithmic development involved a training phase, it's highly probable that contrived samples with known viral concentrations and PCR-confirmed clinical samples with known outcomes would have been utilized for this purpose.

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The OSOM® ULTRA PLUS FLU A&B Test is an in vitro rapid diagnostic immunochromatographic assay intended for the qualitative detection of influenza type A and type B nucleoprotein antigens directly from nasal and nasopharyngeal swab specimens from patients with signs and symptoms of respiratory infection.

It is intended to aid in the rapid differential diagnosis of influenza A and B viral infections. This test is not intended for the detection of influenza C viruses.

A negative test result is presumptive, and it is recommended these results be confirmed by viral culture or an FDA-cleared influenza A and B molecular assay. Negative test results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other patient management decisions.

Performance characteristics for influenza A were established during the US 2018-2019 influenza season when A/H1N1pdm09 and influenza A/H3N2 were the predominant influenza A viruses in circulation, and the influenza B Yamagata and Victoria lineages were in co-circulation. When other influenza A or B viruses are emerging, performance characteristics may vary.

If infection with a novel influenza virus is suspected based on current clinical and epidemiological screening criteria recommended by public health authorities, specimens should be collected with appropriate infection control precautions for novel virulent influenza viruses and sent to state or local health department for testing. Viral culture should not be attempted in these cases unless a BSL 3+ facility is available to receive and culture specimens.

The OSOM® ULTRA PLUS FLU A&B Test consists of a test stick that separately detects influenza A and B. The test procedure requires the solubilization of the nucleoproteins from a swab by mixing the swab in Extraction Buffer. The test stick is then placed in the sample mixture, which then migrates along the membrane surface. If influenza A and/or B viral antigens are present in the sample, it will form a complex with mouse monoclonal IgG antibodies to influenza A and/or B nucleoproteins conjugated to colloidal gold. The complex will then be bound by another a rat anti-influenza A and/or mouse anti-influenza B antibody coated on the nitrocellulose membrane. A pink to purple control line must appear in the control region of the stick for results to be valid. The appearance of a second and possibly a third light pink to purple line in the test line region indicates an A, B or A and B positive result. A visible control line with no test line is a negative result.

The Sekisui Diagnostics OSOM ULTRA PLUS FLU A&B Test is an in vitro rapid diagnostic immunochromatographic assay intended for the qualitative detection of influenza A and B nucleoprotein antigens from nasal and nasopharyngeal swab specimens.

Here's an analysis of the acceptance criteria and study data:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state pre-defined acceptance criteria in terms of numerical thresholds for sensitivity and specificity. Instead, the study results are presented as the device's performance characteristics. Regulatory bodies typically expect high sensitivity and specificity for such diagnostic tests. For the purpose of summarization, we will extract the reported clinical performance as the device's demonstrated performance.

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

• Test Set Sample Size:
  • Prospective study: 1210 evaluable prospective samples.
  • Banked samples: 316 evaluable banked samples.
  • Total evaluable samples for performance evaluation: 1526 samples (1210 prospective + 316 banked).
• Data Provenance:
  • Country of Origin: United States. The prospective study was conducted at 21 point-of-care (POC) sites across the United States.
  • Retrospective or Prospective: The primary clinical study was prospective, collecting samples from January 2019 to May 2019. This prospective dataset was supplemented with 317 banked samples (retrospective) collected from previous influenza seasons due to atypically low prevalence of influenza B in the prospective study period.

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

The document does not explicitly state the number of experts used or their specific qualifications for establishing the ground truth. However, the ground truth was established by "an FDA-cleared molecular test" (a reference method) and further "another FDA-cleared molecular test for discrepant analysis." This implies that the ground truth was determined by validated laboratory methods rather than direct expert interpretation of the rapid test results. The operators at the CLIA waived sites were "untrained operators with no laboratory training or experience," but they were performing the device test, not establishing ground truth.

4. Adjudication Method for the Test Set

The adjudication method used was a "discrepant analysis" involving a second FDA-cleared molecular test.

• For Influenza A: If the OSOM ULTRA PLUS FLU A&B Test results differed from the initial FDA-cleared molecular comparator method, a second FDA-cleared molecular test was used for adjudication. For instance, out of 37 false positive specimens, Flu A was detected in 23 using the second molecular test. For 39 false negative specimens, Flu A was not detected in 7 using the second molecular test.
• For Influenza B: Similarly, FLu B was detected in 3 of 11 false positive specimens using a second FDA-cleared molecular test, and not detected in 2 of 18 false negative specimens using the second test.

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 explicitly described in the provided text in the context of comparing human readers with and without AI assistance. This device is a rapid diagnostic immunochromatographic assay, which is read visually by a single operator (or potentially multiple operators for reproducibility studies, but not in a comparative effectiveness study against AI). The study involved "untrained operators" at POC sites, but their performance was compared against a molecular reference method, not against an AI.

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 a manual, visually interpreted rapid diagnostic test, not an AI-powered algorithm. The device's performance is its standalone performance without human input beyond sample application and visual interpretation. The performance metrics presented (sensitivity, specificity) reflect the device's ability to accurately detect the antigen when operated by intended users (untrained operators).

7. The Type of Ground Truth Used

The ground truth for the clinical performance study was established using:

• An FDA-cleared molecular test (as the primary comparator method).
• Another FDA-cleared molecular test for discrepant analysis.

This indicates a highly reliable laboratory-based ground truth, often considered superior to expert consensus for objective biological markers like viral antigens.

8. The Sample Size for the Training Set

The document does not provide information on a training set sample size. This is expected for laboratory diagnostic devices where development involves analytical studies (LoD, reactivity, specificity) to optimize the assay, followed by clinical validation. 'Training set' is a term primarily used in machine learning and AI development, which does not apply directly to this type of traditional in vitro diagnostic device validation.

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

As there is no mention of a "training set" in the context of AI or machine learning for this device, information on how its ground truth was established is not applicable/provided. The analytical studies (LoD, reactivity, specificity, interference) involve preparing samples with known concentrations of analytes, where the "ground truth" is determined by the preparation method itself and confirmed by standard laboratory techniques.

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The Acucy™ Influenza A&B Test for the rapid qualitative detection of influenza A and B is composed of a rapid chromatographic immunoassay for the direct and qualitative detection of influenza A and B viral nucleoprotein antigens from nasal and nasopharyngeal swabs of symptomatic patients that is automatically analyzed on the Acucy Reader. The Acucy Influenza A&B Test is a differentiated test, such that influenza A viral antigens can be distinguished from influenza B viral antigens from a single processed sample using a single Test Cassette. The test is intended for use with the Acucy System as an aid in the diagnosis of influenza A and B viral infections. The test is not intended for the detection of influenza C viruses. Negative test results are presumptive and should be confirmed by viral culture or an FDA-cleared influenza A and B molecular assay. Negative test results do not preclude influenza viral infection and should not be used as the sole basis for treatment or other patient management decisions.

The Acucy™ Influenza A&B Test is a lateral flow immunochromatographic assay in the sandwich immunoassay format. The Acucy Influenza A&B Test consists of a Test Cassette that detects and differentiates influenza A and influenza B viral antigens from a patient sample. The test sample, a nasal swab or nasopharyngeal swab, is processed to extract nucleoproteins by mixing the swab in Acucy Influenza A&B Extraction Buffer. The mixture is then added to the sample well of the Test Cassette. From there, the sample migrates along the membrane surface. If influenza A or B viral antigens are present, they form a complex with mouse monoclonal antibodies to influenza A and/or B nucleoproteins conjugated to colloidal gold. The complex is then bound by a rat anti-influenza A and/or mouse anti-influenza B antibody coated on the nitrocellulose membrane. The Acucy Reader is an optoelectronic instrument that uses a reflectance-based measurement method to evaluate the line signal intensities in the results window of the Test Cassette. The Reader scans the Test Cassette and measures the absorbance intensity by processing the results using method-specific algorithms. The Acucy Reader displays the test results POS (+), NEG (-), or INVALID on the screen. The results can also be automatically printed on the Acucy Printer if this option is selected.

The document describes the performance of the Acucy™ Influenza A&B Test with the Acucy™ System, which is a rapid in-vitro diagnostic test. Here's a breakdown of the acceptance criteria and the study that proves the device meets them:

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly list "acceptance criteria" for sensitivity and specificity in a separate table. Instead, it presents the achieved performance, which implicitly serves as the successful outcome of the clinical study. The performance is compared against a Composite Reference.

Here's a table summarizing the reported device performance for the combined nasal and nasopharyngeal swab samples from the clinical study, which are the primary results for overall performance:

Other "Acceptance Criteria" implicitly met through other studies:

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

• Sample Size for Test Set:
  • Clinical Performance Study: 1003 evaluable nasal or nasopharyngeal swab samples were included in the primary analysis. A total of 1053 subjects were enrolled initially.
  • Near Cutoff Study: A panel of 84 samples was tested at each of the three CLIA-waived sites, totaling 252 tests.
  • Reproducibility Study: Data for each sample type (e.g., Flu A High Negative) involved 30 replicates per site for 3 sites, totaling 90 replicates per sample type.
• Data Provenance:
  • Country of Origin: The clinical study was conducted at sixteen investigational sites across the U.S. ("across the U.S.").
  • Retrospective or Prospective: The primary clinical study was prospective, conducted during the 2017-2018 influenza season. The "Assay Cutoff" section mentions a clinical dataset comprised of 1252 "prospectively and retrospectively collected samples" was used for ROC analysis, indicating a mix for cutoff optimization, but the main performance evaluation uses prospective data. The Near Cutoff Study was also prospective, conducted during a "normal testing day" over "non-consecutive days."

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

The document does not specify the number or qualifications of experts for establishing ground truth for the clinical test set. Instead, it states that the ground truth was established by a "Composite Reference" consisting of:

• Two FDA-cleared molecular influenza A&B assays
• Cell culture

A sample was considered positive or negative if two or three of these comparative reference methods agreed. This implies an objective, laboratory-based ground truth rather than a panel of human expert review.

4. Adjudication Method for the Test Set

The adjudication method for the clinical test set was a Composite Reference approach.

• "A sample was considered positive for influenza A or influenza B by the Composite Reference if two or three of the comparative reference methods gave a positive result."
• "A sample was considered negative for influenza A or influenza B by the composite reference if two or three of the comparative reference methods gave a negative result."

This is a form of 2-out-of-3 or 3-out-of-3 majority vote from the reference methods, ensuring robust ground truth.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve with AI vs. Without AI Assistance

This document describes an in vitro diagnostic device (a rapid test and its reading system), not an AI-assisted diagnostic imaging device for human readers. Therefore, an MRMC comparative effectiveness study involving human readers and AI assistance is not applicable and was not performed. The "Acucy Reader" is an optoelectronic instrument that automatically processes the lateral flow test, so human interpretation of the test line is not the primary mechanism of reading.

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

Yes, the primary clinical performance evaluation and all analytical studies (LoD, reactivity, specificity, interfering substances) represent standalone performance of the device (Acucy™ Influenza A&B Test with the Acucy™ System). The Acucy Reader is an automated system that "scans the Test Cassette and measures the absorbance intensity by processing the results using method-specific algorithms" and "displays the test results POS (+), NEG (-), or INVALID on the screen." This is purely algorithm/device driven, without human interpretation of the test lines themselves.

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

The ground truth used for the clinical performance evaluation was a Composite Reference based on laboratory methods:

• Two FDA-cleared molecular influenza A&B assays
• Cell culture

This is a robust and objective ground truth commonly used for infectious disease diagnostics.

8. The Sample Size for the Training Set

The document describes a 510(k) submission for a diagnostic test kit involving a lateral flow immunoassay and an optical reader. This is a traditional IVD device, not an AI/ML model that typically requires a large "training set" in the machine learning sense.

However, the "Assay Cutoff" section mentions:

• Initial determination using "contrived influenza A samples, influenza B samples, and negative samples prepared in clinical nasal matrix," tested in "replicates of 60 with two lots of reagents (a total of 360 test results)." This internal testing likely contributed to the initial algorithm development or parameter setting.
• "To validate the primary cutoff values, a clinical dataset comprised of 1252 prospectively and retrospectively collected samples was tested with the Acucy Influenza A&B Test, and Receiver Operator Characteristic (ROC) analysis was performed to determine the optimal values for sensitivity and specificity." This dataset of 1252 samples was used for optimizing and validating the assay cutoffs, which is analogous to a development/validation set in an ML context, though not a "training set" in the iterative learning sense.

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

For the 1252 samples used for ROC analysis and cutoff adjustment:

• The document implies that these samples were "clinical samples," and it's highly probable their true status (positive/negative for Flu A/B) would have been determined by similar reference methods (molecular assays, cell culture) as used for the main clinical study, or other highly accurate laboratory methods.
• For the "contrived samples" used for initial cutoff determination, the ground truth was known by design (i.e., whether the sample was spiked with influenza virus and at what concentration).

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The OSOM® Mono Test is intended for the qualitative detection of infectious monomucleosis heterophile antibodies in serum, plasma or whole blood as an aid in the diagnosis of infectious mononucleosis.

The OSOM Mono Test uses color immunochromatographic dipstick technology with bovine erythrocyte extract coated on the membrane. In the test procedure, serum, plasma or whole blood is mixed with the Diluent. Then the Test Stick is placed in the mixture migrates along the membrane. If the specific IM heterophile antibody is present in the sample, it will form a complex with the bovine erythrocyte extract conjugated color particles. The complex will then be bound by bovine erythrocyte xtract immobilized on the membrane and a visible blue Test Line will appear to indicate a positive result.

The Sekisui Diagnostics OSOM Mono Test is a qualitative diagnostic device for infectious mononucleosis heterophile antibodies. The 510(k) submission [K181436] focuses on a device modification: replacing the prior capillary tube with the Microsafe capillary pipette for whole blood collection.

Here's an analysis of the acceptance criteria and the study performed:

1. Table of Acceptance Criteria and Reported Device Performance

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

The document provides limited detail on sample sizes for the "Compatibility Study". It states "All patients had negative results." The exact number of patients is not specified.

Data provenance: The document does not explicitly state the country of origin or if the data was retrospective or prospective for the non-clinical tests. Given the nature of a device modification focused on a component change, these tests are typically conducted in-house by the manufacturer.

3. Number of Experts Used to Establish Ground Truth and Qualifications

This information is not provided in the document. The studies described are non-clinical, focusing on the functionality of the new pipette, rather than clinical efficacy studies requiring expert interpretation of results.

4. Adjudication Method for the Test Set

This information is not provided in the document. Given that the studies were non-clinical performance tests of a component, an adjudication method typically used for clinical interpretation of diagnostic results would not be applicable.

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. The study described is a non-clinical evaluation of a device component modification. The focus was not on human reader performance with or without AI assistance.

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

This is not applicable. The device, OSOM Mono Test, is an immunochromatographic dipstick test for heterophile antibodies, not an AI algorithm. The studies focused on the physical characteristics and compatibility of a new pipette component.

7. The Type of Ground Truth Used

• Volume Capability Study: The ground truth for this study was the actual dispensed volume measured by a calibrated method, compared against the target range of 50µL and 55µL.
• Compatibility Study: The ground truth for this study was the known negative status of the patient samples, allowing the assessment of whether the new pipette introduced false positive reactions or interfered with negative results.

8. The Sample Size for the Training Set

This is not applicable. The OSOM Mono Test is a rapid diagnostic test based on immunochromatographic principles, not a machine learning algorithm that requires a training set. The "device modification" refers to a physical component (pipette), not an algorithmic change.

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

This is not applicable as there is no training set for this type of device and modification.

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The OSOM iFOB (Immunochemical Fecal Occult Blood) Test is a rapid immunoassay for the qualitative detection of fecal occult blood by laboratories or physicians' offices. It is useful for the detection of human hemoglobin in human fecal samples and is recommended for use as part of routine physical examinations or when lower gastrointestinal disorders are suspected.

The OSOM iFOB (Immunochemical Fecal Occult Blood) Test is a rapid test which can detect the presence of occult blood in human fecal samples by detecting the presence of human hemoglobin (hHb). The OSOM iFOB Test is a qualitative assay that employs immuochromatographic, lateral flow technology. A test kit contains 25 pouched Test Devices, 25 Extraction Reagent vials, 25 conjugate vial tips, and 25 sample collection packs. Tests and Reagents are also available in a 50-test kit without sample collection packs, and sample collection packs are available separately in a package of 50. Negative and positive external controls are provided separately as the OSOM iFOBT Control Kit.

The fecal sample collected using an OSOM iFOB sample collection card is placed into a prefilled vial containing Extraction Buffer. This test solution is then dispensed, through a dropper tip containing human hemoglobin antibody conjugated to latex, into the sample well of the Test Device. The sample migrates across the membrane containing a Test line coated with anti-human hemoglobin antibody and a Control line. If hemoglobin is present at or above the level of detection of the test, an antigen/antibody complex will be formed. The appearance of a visible blue Test line and a red Control line in the result window indicates the presence of human hemoglobin in the sample. A red control line must appear for the results to be valid. If a detectable level of hemoglobin is not present, only the red control line will appear. An invalid test occurs when no control line appears.

The control line serves as an internal procedural control, indicating that the test system is functioning correctly and that the operator added a sufficient volume of sample. In addition to the internal control in each Test Device, external controls are available in a separate OSOM iFOBT Control Kit. The Negative Control (buffer solution) and the Positive Control (hHb in buffer solution) are run in the iFOB Test in the same manner as an extracted fecal sample.

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

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" in a formal, enumerated list with specific thresholds for each performance metric. However, we can infer the acceptance criteria from the study's design and the conclusions drawn about "reproducibility" and "substantial equivalence." The main inferred acceptance criteria revolve around achieving high agreement with expected results and with a predicate device.

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

• Reproducibility and Detection Limit Study:
  • Sample Size: 542 individual test results were reported (325 expected positive, 217 expected negative). This was composed of panels of 15 test samples (3 of each of 5 hemoglobin concentrations: 0, 37.5, 50, 62.5, and 2000 ng/mL hHbA). Each POL operator tested 1 panel on each of 3 lots of the device. The reference site tested the same number of samples as the three external sites. Given 3 POL sites * 3 operators/site * 1 panel/operator/lot * 3 lots = 27 panels. The reference site also tested an equivalent amount. The specific number of unique samples is not directly stated, but the total number of test repetitions is 542.
  • Data Provenance: Retrospective, using spiked fecal samples with known concentrations of human hemoglobin A. The samples are prepared specifically for the study.
• Method Comparison Study:
  • Sample Size: 125 individual test results (75 expected positive, 50 expected negative based on predicate device). This involved 25 replicates of each of the five hemoglobin concentrations (0, 37.5, 50, 62.5, and 2,000 ng/mL hHbA).
  • Data Provenance: Retrospective, using spiked fecal samples with known concentrations of human hemoglobin A. The samples are prepared specifically for the study.
• Sensitivity to Hemoglobin Variants, Hook Effect, Cross-Reactivity, and Interfering Substances:
  • Sample Size: Specific numbers of discrete samples are not explicitly provided for these studies, but they involve testing various concentrations of hHbS, hHbC, potential cross-reactants, and interfering substances with three lots of the OSOM iFOB Test.
  • Data Provenance: Retrospective, using prepared samples (spiked with specific substances) rather than naturally occurring patient samples.

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

• Number of Experts: For the reproducibility study, expert oversight established the testing protocol. However, the ground truth for spiked samples is determined by the known concentration of human hemoglobin A added to the fecal samples, not through expert reading of results.
  • Reproducibility study: "Testing at Sekisui Diagnostics, the reference site, was performed by two experienced laboratory professionals." These professionals performed the testing, but the ground truth (expected positive/negative) was based on the known spiked hemoglobin concentrations. The "intended users" at external POL sites also performed testing, with varying levels of education and work experience.
  • Method Comparison study: The "ground truth" for the OSOM iFOB Test was effectively established by direct comparison to the predicate device (Alfa Instant-View FOB Rapid Test / QuickVue iFOB Test) which itself is cleared as substantially equivalent. The ground truth for the spiked samples themselves was the known hemoglobin concentration.
• Qualifications of Experts: For the Sekisui Diagnostics reference site, "two experienced laboratory professionals" are mentioned. For the external POL sites, it stated "3 intended users per site, with varying levels of education and work experience," implying they are general laboratory or physician office personnel, not necessarily "experts" in establishing ground truth, but rather representative end-users.

4. Adjudication Method for the Test Set

The concept of "adjudication" in the sense of multiple external experts reviewing results to establish a definitive ground truth is not applicable here.

• For the reproducibility and detection limit studies, the ground truth was analytically determined by the known concentrations of spiked human hemoglobin. Samples with 0 and 37.5 ng/mL were expected negative, and samples with 50, 62.5, and 2000 ng/mL were expected positive, based on the device's stated detection level of 50 ng/mL. Any discrepancies between the device result and this analytically derived "expected" result were simply tallied for agreement calculation.
• For the method comparison study, the "ground truth" for comparison was the result obtained by the predicate device (QuickVue iFOB Test) on the same spiked samples, with the ultimate ground truth being the known spiked concentrations.

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

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study comparing human readers with AI assistance versus without AI assistance was not done.

This device (OSOM iFOB Test) is a lateral flow immunoassay for detecting occult blood, not an AI-powered diagnostic system that assists human readers in interpreting complex medical images or data. The "readers" mentioned in the reproducibility study (POL operators) are simply the end-users performing the physical test, not interpreting an AI output.

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

Yes, the performance studies primarily reflect the standalone performance of the device.

The OSOM iFOB Test itself is a rapid immunoassay that produces a visible result (lines on a test strip). While a human operator (the "intended user" or "laboratory professional") has to perform the steps and visually interpret the lines, the core mechanism and output are inherent to the device's chemical and immunochromatographic properties. The studies evaluate the device's ability to accurately provide this result in various conditions, independent of active "human-in-the-loop" interpretive assistance beyond basic observation. The reproducibility study explicitly tested the ability of different users to get consistent results, which is a test of the device's robustness across user variability rather than a human-machine interface evaluation.

7. The Type of Ground Truth Used

The ground truth for all performance studies was primarily analytically determined via known concentrations of spiked human hemoglobin.

• For the reproducibility, detection limit, sensitivity to variants, and hook effect studies, the ground truth was the known concentration of hemoglobin (hHbA, hHbS, hHbC) added to the fecal samples, which then dictated the expected positive or negative result based on the device's detection threshold.
• For the cross-reactivity and interfering substances studies, the ground truth was the known absence or presence of specific interfering/cross-reacting substances along with, for interference, the known presence of hHbA at a critical concentration.
• For the method comparison study, the ground truth was a combination of the known spiked hemoglobin concentrations and the results from a legally marketed predicate device (Alfa Instant-View FOB Rapid Test / QuickVue iFOB Test).

8. The Sample Size for the Training Set

The document does not describe a "training set" in the context of an algorithm or machine learning device.

The OSOM iFOB Test is an immunochromatographic assay, not a device that employs algorithms that require training data. The development of the test (e.g., antibody selection, membrane optimization) would have involved extensive R&D, but this is not typically referred to as a "training set" in the sense used for AI/ML.

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

As there is no "training set" in the context of AI/ML, this question is not applicable. The device's underlying chemistry and biology are its "rules," not a learned algorithm.

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The OSOM® Influenza A&B Test is an in vitro diagnostic immunochromatographic assay intended for the qualitative detection of influenza A and influenza B viral nucleoprotein antigens from nasal swab specimens in symptomatic patients. It is intended to aid in the rapid differential diagnosis of influenza A and/or B viral infections. This test is not intended for the detection of influenza C viruses. A negative test is presumptive and it is recommended these results be confirmed by cell culture. Negative results do not preclude influenza virus infection and should not be used as the sole basis for treatment or other management decisions.

The OSOM® Influenza A&B Test consists of a test stick that separately detects influenza A and B. The test procedure requires the solubilization of the nucleoproteins from a swab by mixing the swab in Extraction Buffer. The test stick is then placed in the sample mixture, which then migrates along the membrane surface. If influenza A and/or B viral antigens are present in the sample, it will form a complex with mouse monoclonal IgG antibodies to Influenza A and/or B nucleoproteins conjugated to colloidal gold. The complex will then be bound by another mouse anti-influenza A and/or B antibody coated on the nitrocellulose membrane. A pink to purple control line must appear in the control region of the stick for results to be valid. The appearance of a second and possibly a third light pink to purple line will appear in the test line region indicating an A, B or A and B positive result.

The provided text describes an update to the package insert of the OSOM® Influenza A&B Test (K092633) to include additional analytical reactivity information for specific H3N2v Influenza A strains. It is not an original submission for a new device, but rather a modification to an already cleared device. As such, the information typically found in an initial 510(k) for device performance and clinical studies demonstrating efficacy for establishing acceptance criteria and proving they are met is largely absent in this document.

However, based on the provided text, here's what can be extracted:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria here is the ability of the OSOM® Influenza A&B Test to react with and detect specific influenza A strains. The stated performance is that the device does react with these strains.

Note: The document specifies that "the performance characteristics of this device with clinical specimens that are positive for these 2009 H1N1 and H3N2v influenza viruses have not been established." This indicates these results are from analytical reactivity studies, not clinical performance studies.

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

The test set consisted of cultured strains of the H3N2v Influenza A virus. The specific sample size (i.e., number of replicates for each strain) is not provided.
The data provenance is from analytical testing (e.g., in vitro laboratory testing) of cultured strains of the H3N2v influenza A virus. The origin of the data is not explicitly stated as a country, but the strains themselves suggest a US origin (West Virginia, Pennsylvania, Minnesota, Kansas, Indiana). The study is retrospective in the sense that the strains were already cultured and tested.

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

This information is not applicable/provided in the document as the study described is an analytical reactivity study using cultured viral strains. The "ground truth" for the test set is the known presence and concentration of the specific influenza virus strains in the cultured samples.

4. Adjudication Method for the Test Set

This information is not applicable/provided as this was an analytical reactivity study, not a clinical study involving human interpretation of results requiring adjudication. The device's reaction (detectable or not) is a direct output.

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

No, an MRMC comparative effectiveness study was not done for this submission. The submission pertains to updating analytical reactivity information for an already cleared in vitro diagnostic device, not evaluating human reader performance.

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

Yes, a standalone performance evaluation was done. The OSOM® Influenza A&B Test is an immunochromatographic assay, which is a rapid diagnostic test that provides a visual result (appearance of a pink to purple line). Its performance in detecting the H3N2v strains was evaluated directly, without human interpretation in the loop beyond observing the presence or absence of the test line.

7. The Type of Ground Truth Used

The ground truth used was the known presence and estimated concentration (EID50/mL or TCID50/mL) of specific cultured influenza A viral strains, often provided by sources like the CDC. This is a form of analytical truth based on established viral culture and quantification methods.

8. The Sample Size for the Training Set

This information is not applicable/provided. The detailed analytical reactivity described is for the test set that demonstrates the device's updated capabilities. For an already cleared device, detailed training set information for its initial development and clearance (K092633) is not part of this specific submission to update labeling. The OSOM® Influenza A&B Test is a lateral flow immunoassay, not a machine learning algorithm, so the concept of a "training set" in the computational sense does not apply. If "training set" refers to samples used during the original development and optimization of the assay, that information is not present here.

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

This information is not applicable/provided for the reasons stated in point 8.

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