(286 days)
The One Step EDDP (Methadone Metabolite) Test Strip is a rapid immunochromatographic assay for the qualitative detection of 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrolidine (EDDP), an inactive metabolite of methadone, at a designated cutoff concentration of 300 ng/mL. This product is used to obtain a visual, qualitative result and is intended for professional use and professionals at point of care sites.
This assay provides only a preliminary 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 indicated.
The One Step EDDP (Methadone Metabolite) Test is an immunoassay based on the principle of competitive binding. Drugs which may be present in the urine specimen compete against the drug conjugate for binding sites on the antibody. During testing, a urine specimen migrates upward by capillary action. EDDP, if present in the urine specimen below 300 ng/mL, will not saturate the binding sites of antibody-coated particles in the test. The antibody-coated particles will then be captured by immobilized EDDP conjugate and a visible colored line will show up in the test line region. The colored line will not form in the test line region if the EDDP level exceeds 300 ng/mL because it will saturate all the binding sites of anti-EDDP antibodies. A drug-positive urine specimen will not generate a colored line in the test line region because of drug competition, while a drug-negative urine specimen containing a drug concentration less than the cut-off will generate a line in the test line region. To serve as a procedural control, a colored line will always appear at the control line region. This confirms sufficient specimen volume, adequate membrane wicking and correct
Here's a summary of the acceptance criteria and the study that proves the device meets them, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implicit from Study) | Reported Device Performance |
|---|---|
| Overall Agreement with GC/MS Analysis (% Agreement) | 98% (538/5549) with a 95% Confidence Interval of (96% - 99%) |
| Accuracy at 50% below cut-off (150 ng/mL EDDP) | >99% (90/90 negative results in spiked samples) |
| Accuracy at 50% above cut-off (450 ng/mL EDDP) | >99% (90/90 positive results in spiked samples) |
Note: The document does not explicitly state "acceptance criteria" with numerical targets. Instead, the "Accuracy" and "Analytical Sensitivity" sections describe the performance that was evaluated and found acceptable. The "Overall Agreement with GC/MS Analysis" of 98% is the primary performance metric for accuracy.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Accuracy Study (Clinical Study): 549 specimens across three clinical sites (183 specimens per site).
- Sample Size for Analytical Sensitivity Study (Spiked Samples): 630 tests (90 tests at each of 7 different EDDP concentrations).
- Data Provenance: The text does not specify the country of origin of the data. The clinical study was performed at "three external clinical study sites," suggesting prospective collection for the purpose of this evaluation. The analytical sensitivity study used "drug-free urine pool[s] spiked with EDDP," indicating laboratory-controlled, prospective data generation.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
- Number of Experts: The document states that the testing for the accuracy study was performed by "3 different employees performing the testing" at the clinical sites for the One Step EDDP Test Strip. However, the ground truth was established by Gas Chromatography/Mass Spectrometry (GC/MS). Therefore, the "experts" in this context would be the technicians or analysts operating the GC/MS.
- Qualifications of Experts: The document does not specify the qualifications of the personnel operating the GC/MS.
4. Adjudication Method for the Test Set
- The document implies a direct comparison of the One Step EDDP Test Strip results to the GC/MS results. There is no mention of an "adjudication method" involving multiple human readers for either the test device results or the GC/MS results. The GC/MS is presented as the reference method ("preferred confirmatory method"), suggesting its results were considered definitive for ground truth.
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 and without AI assistance was not done. This device is a diagnostic test strip, not an AI-assisted diagnostic tool for interpretation by human readers.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- Yes, the performance data presented is for the "One Step EDDP (Methadone Metabolite) Test Strip" itself, without human interpretation influencing the reported accuracy against GC/MS. The test is designed to provide a "visual, qualitative result," which is then compared to the GC/MS. While a human reads the test strip, the reported accuracy reflects the strip's ability to correctly indicate the presence or absence of EDDP at the cutoff, rather than a human's ability to interpret complex images or data. The "Analytical Sensitivity" section, especially with spiked samples, is a clear standalone performance evaluation.
7. The Type of Ground Truth Used
- The primary ground truth used was Gas Chromatography/Mass Spectrometry (GC/MS) analysis. GC/MS is described as the "preferred confirmatory method" and the "reference method" against which the device's accuracy was compared.
8. The Sample Size for the Training Set
- The document does not provide details on a separate "training set" or its sample size. This type of immunoassay device typically does not involve a machine learning algorithm that requires a "training set" in the conventional sense. Its performance is based on the chemical and immunological properties built into the strip. The studies described are for validation/testing.
9. How the Ground Truth for the Training Set Was Established
- As there's no mention of a traditional "training set" for a machine learning algorithm, this question is not applicable. The device's performance is inherently linked to its design and manufacturing specifications.
§ 862.3620 Methadone test system.
(a)
Identification. A methadone test system is a device intended to measure methadone, an addictive narcotic pain-relieving drug, in serum and urine. Measurements obtained by this device are used in the diagnosis and treatment of methadone use or overdose and to determine compliance with regulations in methadone maintenance treatment.(b)
Classification. Class II (special controls). A methadone 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).