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Wondfo Methadone Urine Test (MTD 200) is an immunochromatographic assay for the qualitative determination of Methadone in human urine at a Cut-Off concentration of 200 ng/mL. The test is available in a Dip Card format and a Cup format. This product is only intended for prescription use and is not intended for point-of-care use. The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive.

Wondfo Morphine Urine Test (MOP 100) is an immunochromatographic assay for the qualitative determination of Morphine in human urine at a Cut-Off concentration of 100 ng/mL. The test is available in a Dip Card format and a Cup format. This product is only intended for prescription use and is not intended for point-of-care use. The test provides only preliminary test results. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. GC/MS is the preferred confirmatory method. Clinical consideration and professional judgment should be exercised with any drug of abuse test result, particularly when the preliminary result is positive.

Immunochromatographic assays for Methadone and Morphine Urine Tests use a lateral flow, one step system for the qualitative detection of Methadone and Morphine (target analyte) in human urine. Each assay uses a monoclonal antibody-dye conjugate against drugs with gold chloride and fixed drug-protein conjugates and anti-mouse IgG polyclonal antibody in membranes.

Here's a summary of the acceptance criteria and study details for the Wondfo Methadone Urine Test (MTD200) and Wondfo Morphine Urine Test (MOP100), based on the provided 510(k) summary:

1. Table of Acceptance Criteria and Reported Device Performance

The acceptance criteria are not explicitly stated in a quantitative manner (e.g., "sensitivity must be >X%"). Instead, the precision study demonstrates performance at various concentrations relative to the cut-off, and the comparison study evaluates agreement with GC/MS. The implied acceptance criteria are that the device should accurately classify samples at and above the cut-off as positive, and samples below the cut-off as negative, with high consistency.

Wondfo Methadone Urine Test (MTD200)

Wondfo Morphine Urine Test (MOP100)

2. Sample Size Used for the Test Set and Data Provenance

• Precision Study Test Set:
  • For each drug (MTD200, MOP100) and format (Cup, Dip Card): 3 lots x 9 concentrations x 50 tests/concentration = 1350 tests per drug/format.
  • Total for Precision Study: 1350 (MTD Cup) + 1350 (MTD Dip) + 1350 (MOP Cup) + 1350 (MOP Dip) = 5400 tests.
  • Data Provenance: Samples were prepared by spiking drugs into negative samples. The document states "Each drug concentration was confirmed by GC/MS." Implies prospective preparation in a controlled lab setting, likely within China (country of origin of the submitter).
• Cut-off Verification Test Set:
  • Total of 150 samples per drug/format (equally distributed at -50%, -25%, Cut-Off, +25%, +50% Cut-Off).
  • Tested using three different lots of each device by three different operators.
  • Total for Cut-off Verification: 150 (MTD) + 150 (MOP) = 300 samples (at least for the reporting of performance, though the number of individual tests would be 150 samples * 3 lots * 3 operators = 1350 tests per drug if each operator tested each sample with each lot).
  • Data Provenance: Samples prepared by spiking drugs in negative samples, confirmed by GC/MS. Controlled lab setting.
• Interference Study Test Set:
  • For each interfering substance: spiked into drug-free urine and target drug urine (at 25% below and 25% above Cut-Off level).
  • Tested using three batches of each device for both Dip Card and Cup formats.
  • The exact number of samples (unique urine samples) is not stated, but the number of tests performed would be substantial given the long list of interfering substances.
  • Data Provenance: Controlled lab setting.
• Specificity (Cross-Reactivity) Test Set:
  • Tested "drug metabolites and other components that are likely to interfere."
  • Used three batches of each device for both Dip Card and Cup formats.
  • Data Provenance: Controlled lab setting.
• Effect of Urine Specific Gravity and Urine pH Test Set:
  • Urine samples with specific gravity 1.0001.035 or pH 49, spiked with target drugs at ±25% Cut-Off level.
  • Tested using three batches of each device for both Dip Card and Cup formats.
  • Number of samples not explicitly stated but implies a range of samples covering the specified SG and pH range.
  • Data Provenance: Controlled lab setting.
• Method Comparison Study Test Set:
  • 80 unaltered clinical samples per drug (40 negative and 40 positive).
  • Total for Method Comparison: 80 (MTD) + 80 (MOP) = 160 clinical samples.
  • Data Provenance: "unaltered clinical samples." The country of origin is not explicitly stated, but given the submitter's country, it is likely China. The study is retrospective as the samples were collected and then tested.

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

• For the Precision, Cut-off, Interference, Specificity, and Effect of SG/pH studies, the ground truth was established by GC/MS confirmation of spiked concentrations. This implies a skilled analytical chemist or laboratory technician performed these confirmations.
• For the Method Comparison Study, the ground truth was GC/MS results. "GC/MS is the preferred confirmatory method." The qualifications of the personnel performing the GC/MS are not specified beyond this.

4. Adjudication Method for the Test Set

• There is no explicit adjudication method described for the interpretation of the Wondfo device results in the method comparison study. The study states "Operators ran 80 ... clinical samples. The samples were blind labeled and compared to GC/MS results."
• There were three "laboratory assistants" (referred to as Viewer A, B, C) who presumably interpreted the Wondfo test results. Each viewer's results are reported individually, indicating no consensus or adjudication process among them for the device readings. The comparison is then made against the single 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, an MRMC comparative effectiveness study was not done.
• This study is a comparison of a diagnostic device (Wondfo test kit) against a gold standard (GC/MS), interpreted visually by human "viewers" or "operators." It does not assess human reader improvement with or without AI assistance, as the device itself is a simple immunochromatographic assay, not an AI-based system.

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

• Yes, in effect, a standalone performance was demonstrated for the Wondfo device, with human interpretation being the "standalone algorithm" here. The "operators" or "viewers" simply read the device results. There is no complex human-in-the-loop interaction beyond visual interpretation of lines. The performance metrics presented (precision, specificity, comparison to GC/MS) reflect the device's inherent analytical characteristics when interpreted by a human, rather than the impact of an "algorithm only" in the sense of a machine learning model.

7. The Type of Ground Truth Used

• The primary ground truth used across all studies (Precision, Cut-off, Interference, Specificity, Effect of SG/pH, and Method Comparison) was the Gas Chromatography/Mass Spectrometry (GC/MS) results.
• For spiked samples, the concentration was also analytically confirmed by GC/MS.

8. The Sample Size for the Training Set

• This information is not applicable as the Wondfo Methadone/Morphine Urine Test is an immunochromatographic assay, not an AI or machine learning-driven device that requires an explicit training set. The manufacturing process and quality control for the test strips would be developed using internal data and R&D, but this is not typically referred to as a "training set" in the context of AI/ML.

9. How the Ground Truth for the Training Set Was Established

• This information is not applicable for the reasons stated above (not an AI/ML device).

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