(321 days)
Wondfo One Step Buprenorphine Urine Test Strip, Wondfo One Step Oxycodone Urine Test Strip, and Wondfo One Step Propoxyphene Urine Test Strip are intended for the qualitative determination of Buprenorphine, Oxycodone, d-Propoxyphene at the specific cut-off concentration in human urine. They are intended for healthcare professionals in a central laboratory setting only and that it is not for use in point-of-care settings.
Immunochromatographic assay for drugs of abuse using a lateral flow, one step system for the qualitative detection of specific drugs in human urine. Each assay uses a monoclonal antibody-dye congugate from mouse against drug with gold chloride and fixed drug-protein conjugate and anti-mouse lgG polyclonal antibody in membrane.
This document describes the validation study for the Wondfo One Step Buprenorphine Urine Test Strip, Wondfo One Step Oxycodone Urine Test Strip, and Wondfo One Step Propoxyphene Urine Test Strip.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria are implied by the need to demonstrate substantial equivalence to predicate devices, which generally involves showing high agreement rates with a gold standard method. Specific numerical acceptance criteria are not explicitly stated in the provided document. However, the reported performance metrics (percentage agreement and 95% Confidence Intervals) indicate the device's accuracy. We will present the lowest reported agreement rates across all viewers for each drug as representative performance.
| Drug | Acceptance Criteria (Implied) | Reported Device Performance (Lowest %) (95% CI) |
|---|---|---|
| Buprenorphine | High agreement with GC-MS for positives and negatives. | Positive Agreement: 90% (74.5% - 100%) |
| Negative Agreement: 95% (79.5% - 100%) | ||
| Oxycodone | High agreement with GC-MS for positives and negatives. | Positive Agreement: 90% (74.5% - 100%) |
| Negative Agreement: 95% (79.5% - 100%) | ||
| Propoxyphene | High agreement with GC-MS for positives and negatives. | Positive Agreement: 87.5% (72.0% - 100%) |
| Negative Agreement: 95% (79.5% - 100%) |
2. Sample size used for the test set and the data provenance
- Test Set Sample Size:
- For each drug (Buprenorphine, Oxycodone, Propoxyphene): 80 clinical urine specimens (40 negative and 40 positive).
- Total test samples across all three drugs: 240 specimens (80 for each drug).
- Data Provenance:
- Country of Origin: Not explicitly stated, but the submission is from Guangzhou Wondfo Biotech Co., Ltd. in Guangzhou, P.R. China, and samples were partly from "Shenzhen Drug Addiction Recovery Center," suggesting data originated from China.
- Retrospective or Prospective: Retrospective. The samples were "clinical urine specimens" and existing "drug clinical samples" were used.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts
- Number of Experts for Ground Truth: Not applicable in the traditional sense of human experts interpreting images or complex data. The ground truth was established by Gas Chromatography-Mass Spectrometry (GC-MS) analysis, which is a highly accurate analytical method, not human interpretation.
- Qualifications of Experts (for device reading): The Wondfo tests were read by "three viewers." No specific qualifications for these viewers are provided (e.g., "radiologist with 10 years of experience").
4. Adjudication method for the test set
- The document states, "Each Wondfo test was read by three viewers." However, it presents separate agreement rates for each "Viewer A," "Viewer B," and "Viewer C." This indicates that there was no explicit adjudication method mentioned to combine or reconcile differences between the three viewers' readings to establish a single device result per sample. Each viewer's interpretation was compared independently against the GC-MS ground truth.
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 MRMC comparative effectiveness study was done in the context of human readers improving with AI assistance. This study evaluates the standalone performance of the test strips, which are non-AI diagnostic devices. The "readers" are interpreting the strip results, not using AI.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done
- Yes, a standalone study was done. The Wondfo One Step Urine Test Strips are lateral flow immunochromatographic assays. Their "performance" is inherently standalone, as they produce a visual result (a line or lack thereof) without an AI algorithm or human intervention to process the result beyond visual interpretation. The reported agreement percentages are for the interpretation of the test strip's result against the GC-MS ground truth.
7. The type of ground truth used
- The ground truth used was Gas Chromatography-Mass Spectrometry (GC-MS) analysis. This is an analytical chemistry method that provides definitive identification and quantification of substances, making it a highly reliable gold standard for drug detection in urine.
8. The sample size for the training set
- Not applicable. This device is an immunochromatographic assay, not an AI/machine learning model. Therefore, there is no "training set" in the context of an algorithm learning from data. The reference to "Originally 25 drug clinical samples of varying concentrations were from Cutoff Value section" and "10 negative samples and additional 45 clinical samples were from Shenzhen Drug Addiction Recovery Center" within the "Sample description" for the test set seems to describe the origin of samples for the performance evaluation, not a separate training phase.
9. How the ground truth for the training set was established
- Not applicable. As there is no training set for an AI/machine learning algorithm, the concept of establishing ground truth for a training set does not apply. The ground truth for the performance evaluation samples was established by GC-MS.
§ 862.3650 Opiate test system.
(a)
Identification. An opiate test system is a device intended to measure any of the addictive narcotic pain-relieving opiate drugs in blood, serum, urine, gastric contents, and saliva. An opiate is any natural or synthetic drug that has morphine-like pharmocological actions. The opiates include drugs such as morphine, morphine glucoronide, heroin, codeine, nalorphine, and meperedine. Measurements obtained by this device are used in the diagnosis and treatment of opiate use or overdose and in monitoring the levels of opiate administration to ensure appropriate therapy.(b)
Classification. Class II (special controls). An opiate 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).