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The Propoxyphene Enzyme Immunoassay is a homogeneous enzyme immunoassay with a 300 ng/mL cutoff. The assay is intended for use in the qualitative and semi-quantitative analyses of propoxyphene in human urine. The assay is designed for professional use with a number of automated clinical chemistry analyzers.

The Propoxyphene Enzyme Immunoassay provides only a preliminary analytical test result. A more specific alternative chemical method must be used to obtain a confirmed analytical result. Gas chromatography/mass spectrometry (GC/MS) is the preferred confirmatory method. Clinical consideration and professional judgement should be applied to any drug-ofabuse test result, particularly when preliminary positive results are used.

LZI's Propoxyphene Enzyme Immunoassay is a ready-to-use, liquid reagent, homogeneous enzyme immunoassay. The assay uses specific antibody that can detect propoxyphene in human urine with minimal cross-reactivity to various, common prescription drugs and abused drugs.

The assay is based on competition between propoxyphene labeled with glucose-6-phosphate dehydrogenase (G6PDH) enzyme, and free drug from the urine sample for a fixed amount of specific antibody. In the absence of free drug from the urine sample the specific antibody binds to the drug labeled with G6PDH enzyme causing a decrease in enzyme activity. The G6PDH enzyme activity is determined spectrophotometrically at 340 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.

The provided text is a 510(k) summary for the Lin-Zhi International, Inc.'s Propoxyphene Enzyme Immunoassay. It describes the device, its intended use, and a comparison to a predicate device, along with performance characteristics. However, it does not provide detailed acceptance criteria in the typical format of a threshold that needs to be met (e.g., "sensitivity must be >90%"). Instead, it presents performance data for the new device alongside information from the predicate device (or states "No data available" for the predicate). The "acceptance criteria" are implied by the comparison to the predicate device and the conclusion that results were "acceptable."

Therefore, the table below reflects what can be extracted. Points 2 through 9 of your request cannot be fully answered from this document because it describes an in vitro diagnostic (IVD) assay, not a medical device that undergoes a typical "study" with a "test set" and "ground truth established by experts" in the way one might evaluate an AI/imaging device. The performance characteristics for IVD assays primarily focus on analytical performance like precision, sensitivity, accuracy against a reference method (like GC/MS), and specificity (cross-reactivity).

Acceptance Criteria and Device Performance

Study Details (as inferable from the document for this IVD device):

1. Sample size used for the test set and the data provenance:

   • Accuracy (Qualitative): 57 positive samples were confirmed by GC/MS. The total number of samples compared against a commercial EIA was 126.
   • Provenance: Not explicitly stated, but typically clinical laboratory samples. No country of origin specified. Retrospective/Prospective not specified, but likely retrospective testing of banked samples or samples collected for validation.
   • Precision and Analytical Recovery: Not specified but typically involves multiple replicates of spiked samples and controls.

2. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:

   • Not applicable in the typical sense for this IVD device. The "ground truth" for chemical analysis like this is established by a reference method.
   • Reference Method for Accuracy: Gas Chromatography/Mass Spectrometry (GC/MS) is cited as the preferred confirmatory method and was used for a portion of the accuracy study. GC/MS is an analytical chemistry technique, not an expert review.

3. Adjudication method (e.g. 2+1, 3+1, none) for the test set:

   • Not applicable. The "ground truth" is determined by a definitive analytical method (GC/MS).

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:

   • Not applicable. This is an in vitro diagnostic assay for drug detection, not an imaging or AI-driven diagnostic device that involves human readers/interpreters.

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

   • This is a standalone assay (chemical test), not an algorithm. Its performance is determined by the chemical reactions and spectrophotometric measurements. There is no "human-in-the-loop" performance component beyond interpreting the assay's final quantitative or qualitative result, which is common for all lab tests. The device itself performs the analysis without human interpretation of raw data beyond reading the instrument output.

6. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):

   • The primary ground truth for accuracy was established using a reference analytical method, specifically Gas Chromatography/Mass Spectrometry (GC/MS).

7. The sample size for the training set:

   • Not applicable. As a chemical immunoassay, there is no "training set" in the machine learning sense. The assay is developed based on chemical principles and optimized through reagent formulation and calibration.

8. How the ground truth for the training set was established:

   • Not applicable. No "training set" in the machine learning sense. The assay's performance characteristics are inherent to its chemical design. Calibration would have used known concentration standards.

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