(143 days)
Syntron's QuikStrip One Step Methamphetamine assay is a rapid, qualitative, competitive binding immunoassay for the determination of methamphetamine in urine. The test provides only preliminary data which should be confirmed by other methods such as gas chromatography/mass spectrophotometry (GCMS). Clinical considerations and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are indicated. Syntron's Quikstrip One Step Methamphetamine Test is not intended to monitor drug levels, but only screen urines for the presence of methamphetamine and its metabolites.
Syntron's QuikStrip One Step Methamphetamine Test consists of a chromatographic absorbent device in which the drug or drug metabolites in the sample compete with a drug conjugate immobilized on a porous membrane support for the limited antibody sites. As the test sample flows up through the absorbent device, the labeled antibody-dye conjugate binds to the free drug in the specimen forming an antibody:antigen complex. This complex competes with immobilized antigen conjugate in the positive reaction zone and will not produce a magenta color band when the drug is above the detection level of 500 ng/ml. Unbound dye conjugate binds to the reagent in the control zone, producing a magenta color band, demonstrating that the reagents and device are functioning correctly.
Acceptance Criteria and Study Details for QuikStrip One Step Methamphetamine Test
The QuikStrip One Step Methamphetamine Test is a qualitative, competitive binding immunoassay for the determination of methamphetamine in urine. Its intended use is for medical/forensic screening.
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for this device appear to be implicitly set by the performance observed in the in-house testing and clinical trial, demonstrating high agreement with a reference method (Syva EMIT® II and GC/MS confirmation).
| Metric | Acceptance Criteria (Implied) | Reported Device Performance (In-house) | Reported Device Performance (Clinical Trial) |
|---|---|---|---|
| Relative Sensitivity (Agreement within positives) | High (e.g., ≥95%) | 1.00 (100%) | 100% |
| Relative Specificity (Agreement within negatives) | High (e.g., ≥95%) | 1.00 (100%) | 97.7% |
| Accuracy | High (e.g., ≥95%) | 100% | 98.68% |
Note: The document does not explicitly state numerical acceptance criteria prior to presenting the results. The 100% and near 100% performance suggests that these high levels of agreement were deemed acceptable for the device's intended use as a screening tool.
2. Sample Size and Data Provenance
- Test Set (Clinical Trial): 305 samples.
- Data Provenance: Not explicitly stated (e.g., country of origin, retrospective or prospective). However, the description of "clinical trial" suggests prospective data collection in a clinical setting. The reference to "in-house testing" implies internal data for initial validation.
3. Number, Qualifications, and Adjudication Method of Experts for Ground Truth
The ground truth was established by comparison to reference methods, not directly by human expert interpretation of the device's results.
- Number of Experts: Not applicable in the context of human interpretation of the device.
- Qualifications of Experts: Not applicable.
- Adjudication Method: Not applicable.
4. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- Was an MRMC study done? No. This device is an in-vitro diagnostic (IVD) test where the result is determined by the test strip itself (presence or absence of a color band), not by human interpretation or reading that would vary between individuals needing such a study.
- Effect size of AI vs. without AI assistance: Not applicable. The device is a standalone chemical/immunological test, not an AI-assisted diagnostic tool.
5. Standalone Performance Study
- Was a standalone study done? Yes. Both the "in-house testing" and the "clinical trial" represent standalone performance evaluations of the QuikStrip One Step Methamphetamine Test. The results presented in the table above reflect this standalone performance against reference methods.
6. Type of Ground Truth Used
- Type of Ground Truth:
- Syva EMIT® II: This is a widely accepted immunoassay for drug screening, serving as an initial comparative method.
- GC/MS (Gas Chromatography/Mass Spectrophotometry): This is the gold standard for confirmatory drug testing, offering highly accurate and specific identification and quantification of substances. All positive samples by either screening method (QuikStrip or EMIT) were confirmed by GC/MS. This indicates GC/MS was the ultimate ground truth for positive samples.
7. Sample Size for the Training Set
- The document does not explicitly mention a separate "training set" in the context of an algorithm or machine learning device. For an immunoassay, the "training" usually refers to the development and optimization of the reagents and assay parameters through iterative laboratory testing. The sample sizes mentioned (in-house and clinical trial) are for validation and performance assessment.
8. How the Ground Truth for the Training Set Was Established
- As above, the concept of a "training set" ground truth for an immunoassay is not directly applicable in the same way as for an AI/ML algorithm. The assay's performance characteristics (e.g., cutoff concentration, cross-reactivity) are established during development and verified against known samples (either spiked samples or characterized clinical specimens) using reference methods like GC/MS.
§ 862.3100 Amphetamine test system.
(a)
Identification. An amphetamine test system is a device intended to measure amphetamine, a central nervous system stimulating drug, in plasma and urine. Measurements obtained by this device are used in the diagnosis and treatment of amphetamine use or overdose and in monitoring levels of amphetamine to ensure appropriate therapy.(b)
Classification. Class II (special controls). An amphetamine 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).