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The Chemtrue® Drug Screen Cup Tests are rapid lateral flow immunoassays for the qualitative detection of Buprenorphine, Amphetamine, Cocaine, Morphine 300, Methamphetamine, Phencyclidine, Benzodiazepines, Barbiturates, Ecstasy, Methadone, Oxycodone and Tricyclic Antidepressants drugs in human urine. The test cut-off concentrations and the compounds the tests are calibrated to are as follows:

The Chemtrue® Drug Screen Cup Tests panel can consist of any combination of the above listed drug analytes.

The tests are intended for prescription and Over-The-Counter (OTC) use.

The tests provide only a preliminary result. A more specific alternative chemical method must be used in order to obtain a confirmed assay result. Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Mass Spectrometry (LC/MS) are the preferred confirmatory methods. Clinical consideration and professional judgment should be applied to any drugs of abuse test result, particularly when preliminary positive results are indicated.

The tests are not intended to differentiate between drugs of abuse and prescription use of Benzodiazepines, Buprenorphine, Oxycodone and Tricyclic Antidepressants. There are no uniformly recognized cutoff concentration levels for these drugs in urine.

The Chemtrue Drug Screen Cup Tests with OPI 2000 are rapid lateral flow immunoassays for the qualitative detection of Buprenorphine, Amphetamine, Cocaine, Marijuana, Opiates 2000, Methamphetamine, Phencyclidine, Benzodiazepines, Barbiturates, Ecstasy, Methadone, Oxycodone and Tricyclic Antidepressants drugs in human urine. The test cut-off concentrations and the compounds the tests are calibrated to are as follows:

The Chemtrue Drug Screen Cup Tests with OPI 2000 panel can consist of any combination of the above listed drug analytes.

The tests are intended for prescription and Over-The-Counter (OTC) use.

The tests provide only a preliminary result. A more specific alternative chemical must be used in order to obtain a confirmed assay result. Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Mass Spectrometry (LC/MS) are the preferred confirmatory methods. Clinical consideration and professional judgment should be applied to any drugs of abuse test result, particularly when preliminary positive results are indicated.

The tests are not intended to differentiate between drugs of abuse and prescription use of Benzodizzepines, Buprenorphine, Oxycodone and Tricyclic Antidepressants. There are no uniformly recognized cutoff concentration levels for these drugs in urine.

The Chemtrue® Drug Screen Cup Tests are colloidal gold based lateral flow immunoassays for the rapid, qualitative detection of drugs of abuse in human urine. The tests are single-use, in vitro diagnostic devices, which come in the Cup format, as indicated by the test name.

The provided document describes the performance characteristics of the Chemtrue® Drug Screen Cup Tests and Chemtrue® Drug Screen Cup Tests with OPI 2000.

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

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state "acceptance criteria" as a pass/fail threshold. Instead, it presents the results of reproducibility, specificity, interference, and method comparison studies. The performance is reported in terms of agreement with GC/MS (reference method) and the percentage of accurate results at various concentrations (negative, 50%, 75%, 125%, 150% of cutoff). For the purpose of this response, "reported device performance" will be directly extracted from the provided tables.

Acceptance Criteria (Implied) and Reported Device Performance for Method Comparison (Accuracy) Study:

The document implies an acceptance criterion for accuracy based on the "Agreement" percentage. For most analytes, the agreement with the GC/MS reference method is 98% or 100%. For discordant results, it is noted that these were confirmed at the drug cutoff level.

Acceptance Criteria (Implied) and Reported Device Performance for OTC Lay-user Accuracy and Usability Studies:

The implied acceptance criterion here is 100% agreement for all drug concentrations (No Drug Present, 50% of cutoff, 75% of cutoff, 125% of cutoff, 150% of cutoff). For all analytes except THC, 100% agreement was reported across all concentration levels tested. THC showed 90% agreement at 75% of cutoff.

| Analyte | Cutoff (ng/mL) | Agreement (No Drug present) | Agreement (50% cutoff) | Agreement (75% cutoff) | Agreement (125% cutoff) | Agreement (150% cutoff) |
|---|---|---|---|---|---|
| AMP | 1000 | 100% | 100% | 100% | 100% | 100% |
| BAR | 300 | 100% | 100% | 100% | 100% | 100% |
| BZO | 300 | 100% | 100% | 100% | 100% | 100% |
| BUP | 10 | 100% | 100% | 100% | 100% | 100% |
| COC | 300 | 100% | 100% | 100% | 100% | 100% |
| MDMA | 500 | 100% | 100% | 100% | 100% | 100% |
| MET | 1000 | 100% | 100% | 100% | 100% | 100% |
| MTD | 300 | 100% | 100% | 100% | 100% | 100% |
| MOR | 300 | 100% | 100% | 100% | 100% | 100% |
| OPI | 2000 | 100% | 100% | 100% | 100% | 100% |
| OXY | 100 | 100% | 100% | 100% | 100% | 100% |
| PCP | 25 | 100% | 100% | 100% | 100% | 100% |
| TCA | 1000 | 100% | 100% | 100% | 100% | 100% |
| THC | 50 | 100% | 100% | 90% | 100% | 100% |

2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)

• Method Comparison Studies (Accuracy Study):

  • Sample Size: "On average of 85 clinical specimens for each drug test and a total of 586 samples were tested."
  • Data Provenance: The document states "blind-labeled clinical specimen correlation study". It does not specify the country of origin of the data or explicitly state if it was retrospective or prospective, but the use of "clinical specimens" suggests these were real-world samples.

• Reproducibility (Precision) Studies:

  • Sample Size: For each analyte and concentration level, 30 devices were tested (3 operators * 3 lots * 10 replicates for each level of Negative, 50%, 75%, Cutoff, 125%, 150% of the cutoff). The tables show n=210 for Negative concentration and n=30 for each of the other concentration levels (50%, 75%, Cutoff, 125%, 150% of cutoff) over 10 non-consecutive days.
  • Data Provenance: The study used "GC/MS confirmed drug spiked urine controls." This indicates artificially prepared samples by spiking drugs into drug-free urine, not clinical specimens. The location or type of institution where this was performed is not specified.

• OTC Lay-user Accuracy and Usability Studies:

  • Sample Size: 100 intended lay-users participated.
  • Data Provenance: "GC/MS confirmed urine samples" were used. These samples were artificially prepared by "spiking drugs into drug-free urine pool" and aliquoted into individual blind-labeled containers. The study was conducted at "three (3) intended user sites," implying it was conducted in a real-world or simulated real-world setting for OTC use, but the origin of the drug-free urine or spiking drugs is not detailed.

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

The ground truth for all performance studies (reproducibility, method comparison, and OTC lay-user accuracy) was established using Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Mass Spectrometry (LC/MS) as the preferred confirmatory methods.

GC/MS and LC/MS are analytical chemistry techniques that provide definitive identification and quantification of substances. Therefore, the "ground truth" is based on the results of these highly accurate chemical methods, rather than human expert interpretation of images or clinical findings. The expertise implicitly lies in the technicians and analytical instruments performing the GC/MS/LC/MS analysis. No specific "number of experts" or their "qualifications" like radiologists with X years of experience are applicable here, as it's a lab-based chemical assay validation.

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

The concept of a "2+1" or "3+1" adjudication method is typically used in studies where multiple human readers interpret results and a consensus or tie-breaker is needed, especially in imaging studies.

In this context, the adjudication method is "none" for human readers. Any "adjudication" between the device's results and the ground truth was done by comparing the device's qualitative positive/negative result against the quantitative GC/MS/LC/MS cut-off value. If there was a discrepancy (discordant result), the GC/MS result was considered the definitive truth. The "blind-labeled clinical specimen correlation study" implies that the device results were compared after the GC/MS truth was known, or at least independently, to determine agreement.

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, a multi-reader multi-case (MRMC) comparative effectiveness study was not done.

This type of study is relevant for evaluating human performance improvements with AI assistance, typically in diagnostic imaging where human readers interpret and classify cases. The Chemtrue® Drug Screen Cup Tests are in vitro diagnostic devices (qualitative immunoassays) for drug detection in urine, interpreted visually by a single user. There is no "AI assistance" involved in the interpretation process described in this document, nor is there a cohort of human readers making independent diagnostic judgments that would then be compared.

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

Yes, a standalone performance study was done in essence. The "Reproducibility (Precision) Studies," "Specificity Study," and "Interference" studies examine the intrinsic performance of the device (immunoassay) itself under controlled conditions and against known reference methods (GC/MS). The tables showing detection rates at various concentrations and cross-reactivity are direct measures of the device's standalone performance.

The "Method Comparison Studies" (Accuracy study, section H.5) also evaluate the device's performance against the GC/MS reference method. While "three operators performed the testing," their role was to visually interpret the test lines, which is a direct readout of the device's chemical reaction. The accuracy is reported as the device's performance against the gold standard, not the operators' modified performance.

The "OTC Lay-user Accuracy and Usability Studies" (section H.6) assess "lay-user accuracy," which means how accurately un-trained individuals could read and interpret the device standalone results. This is still a standalone performance assessment of the device, albeit under user-influenced conditions.

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

The primary type of ground truth used for performance evaluation was Gas Chromatography/Mass Spectrometry (GC/MS) or Liquid Chromatography/Mass Spectrometry (LC/MS). These are highly accurate and definitive analytical chemistry methods for identifying and quantifying substances in a sample.

• For reproducibility studies, GC/MS confirmed drug spiked urine controls were used.
• For method comparison studies, the device was compared to the GC/MS Reference Method using blind-labeled clinical specimens.
• For OTC lay-user studies, GC/MS confirmed urine samples (spiked into drug-free urine pool) were used.

8. The sample size for the training set

The document describes the validation studies for the device but does not specify or mention a "training set" in the context of machine learning or AI algorithm development. The device is a lateral flow immunoassay, which relies on chemical reactions and visual interpretation, not on trained algorithms that require a separate training dataset.

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

As there is no mention of a "training set" for an AI or machine learning algorithm in this document (the device is a qualitativeunoassay), this question is not applicable. The ground truth for the device's validation was established using GC/MS/LC/MS as detailed above.

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