(107 days)
This device is a one-step intended to provide qualitative rapid detection of methylenedioxymethamphetamine (MDMA, or Ecstasy, XTC) in human urine at a cut-off concentration of 500ng/ml. It is for health care professional use only.
This test provides only a preliminary analytical test result. A more specific alternate chemical method must be used in order to obtain a confirmed analytical result. Gas Chromatography/Mass Spectrometry (GC/MS) is the preferred confirmatory method. Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.
A one-step lateral flow chromatographic immunoassay. The test strip in the device includes 1) a conjugate pad containing colloidal gold coupled with mouse anti-MDMA antibody; 2) nitrocellulose membrane containing a test line (T line) coated with MEMA-BSA and a control line (C line) coated with Goat anti mouse antibody.
Here's a summary of the acceptance criteria and the study details for the Instant-View™ MDMA (Ecstasy, XTC) Urine Test, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Accuracy (Overall Agreement) | 97.5% agreement with MDMA GC/MS data. |
| Accuracy (Agreement at levels below 75% of cutoff and above cutoff) | 100% agreement with MDMA GC/MS data. |
| Reproducibility | 97.5% agreement across four evaluation sites. |
| Specificity (Non-cross-reactivity with other compounds at 100 µg/ml) | Most structurally related compounds showed no cross-reactivity or interference. |
| Specificity (Cross-reactivity with structurally related amphetamines) | Methylenedioxyampphetamine (MDA) at 2000 ng/ml and Methylenedioxyethylamphetamine (MDEA) at 1000 ng/ml showed cross-reactivity. |
| Cut-off Concentration | Qualitative detection at a cut-off of 500 ng/ml. |
Study Details
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1. Sample size used for the test set and the data provenance:
- Sample Size: 80 clinical urine specimens.
- Data Provenance: Retrospective, with no specific country of origin mentioned beyond "clinical urine specimens."
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2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This information is not provided in the text. The ground truth was established by Gas Chromatography/Mass Spectrometry (GC/MS) data, which is an analytical method, not directly dependent on expert interpretation in the same way as, for example, reading a medical image.
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3. Adjudication method for the test set:
- None stated directly for test set results. The comparison was against objective GC/MS data. Discrepancies were noted but no human adjudication process for those discrepancies is described.
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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. This device is a rapid diagnostic immunoassay, not an AI-assisted diagnostic tool for human readers. Therefore, an MRMC study is not applicable.
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5. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Yes, for the accuracy study. The device itself produced results that were then compared to the GC/MS ground truth. While it's a qualitative test, the performance metrics (agreement percentage) reflect the device's standalone capability.
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6. The type of ground truth used:
- Pathology/Outcomes Data: The ground truth was established using Gas Chromatography/Mass Spectrometry (GC/MS) data. This is a highly accurate and commonly accepted confirmatory method for drug testing, often considered the gold standard.
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7. The sample size for the training set:
- Not explicitly stated. The document describes "accuracy studies" and "reproducibility studies" but does not differentiate a specific "training set" for the device, as it is a lateral flow immunoassay that operates based on a fixed chemical design, not a machine learning algorithm.
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8. How the ground truth for the training set was established:
- Not applicable for a training set as the device is a chemical immunoassay, not an algorithm that undergoes a training phase with labeled data in the conventional sense of AI. The performance validation was against GC/MS data on clinical specimens.
§ 862.3610 Methamphetamine test system.
(a)
Identification. A methamphetamine test system is a device intended to measure methamphetamine, a central nervous system stimulating drug, in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of methamphetamine use or overdose.(b)
Classification. Class II (special controls). A methamphetamine test system is not exempt if it is intended for any use other than employment or insurance testing or is intended for Federal drug testing programs. The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9, provided the test system is intended for employment and insurance testing and includes a statement in the labeling that the device is intended solely for use in employment and insurance testing, and does not include devices intended for Federal drug testing programs (e.g., programs run by the Substance Abuse and Mental Health Services Administration (SAMHSA), the Department of Transportation (DOT), and the U.S. military).