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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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The Propoxyphene assay is used for the qualitative analysis of propoxyphene in human urine with a cutoff of 300 ng/mL for used a clinical laboratories. Measurements obtained by this device are used in the diagnosis and treatment of propoxyphene use or overdose. The Propoxyphene assay is calibrated with propoxyphene and will detect propoxyphene and metabolites and analogs. The Propoxyphene assay provides only a preliminary analytical test result. A more specific alternate chemical method must be 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 results are used.

Propoxyphene is an in vitro diagnostic assay for the qualitative analysis of Propoxyphene in human urine. The assay is a homogeneous enzyme, immunoassay with a 300 ng/ml, cutoff. The assay is based on competition between drug in the specimen and drug labeled with the enzyme glucose-6-phosphate dehydrogenase (G6PDH) for antibody binding sites. Enzyme activity decreases upon binding to the antibody, so the drug concentration in the specimen can be measured in terms of enzyme activity. Active enzyme converts NAD to NADH, resulting in an absorbance change that can be measured spectrophotometrically.

The provided text describes the Propoxyphene assay, an in vitro diagnostic assay for the qualitative analysis of Propoxyphene in human urine. The study conducted aims to demonstrate its substantial equivalence to the Emit® II Propoxyphene assay (K923873).

Here's an analysis of the acceptance criteria and study information:

1. Table of Acceptance Criteria and Reported Device Performance

The document doesn't explicitly state "acceptance criteria" for the Propoxyphene assay in a tabular format with numerical targets. Instead, it defines the performance characteristics and demonstrates substantial equivalence to a predicate device. The primary performance metric reported is concordance (agreement) with the predicate device.

Note on "Acceptance Criteria": For substantial equivalence claims, the acceptance criteria are often implicitly tied to demonstrating that the new device performs "as well as" or "similarly to" the predicate device for its intended use. Here, 99% agreement with the predicate device appears to be the key performance indicator used to support substantial equivalence.

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

• Sample Size for Test Set: Not explicitly stated as a single number for the comparative performance study. The text mentions "The clinical specimens tested ranged from 404 to 56,662 ng/mL," implying that multiple clinical specimens were used. However, the exact number tested for the 99% concordance is not provided.
• Data Provenance: Not specified (e.g., country of origin). The study used "clinical specimens." It is not stated whether the data was retrospective or prospective, but clinical specimens usually imply retrospective collection for such comparative studies.

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

• Number of Experts: Not applicable. For this type of in vitro diagnostic assay, the "ground truth" for the test set is established by a reference method, not by human experts.
• Qualifications of Experts: N/A.

4. Adjudication Method for the Test Set

• Adjudication Method: Not applicable. The ground truth is established by a reference method (GC/MS for confirmatory analysis, and the predicate device for comparative performance), not by a consensus of experts. Discrepancies between the new device and the predicate device were resolved by GC/MS (e.g., the one discordant sample was confirmed by GC/MS).

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

• MRMC Study: No, this is an in vitro diagnostic device for analyte detection, not an imaging analysis or decision support system that involves human readers interpreting cases. Therefore, a multi-reader multi-case (MRMC) comparative effectiveness study is not relevant here.

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

• Standalone Performance: Yes, the device's performance characteristics (e.g., concordance, precision, cutoff, limit of detection) are reported for the instrument-based assay itself, operating without human interpretation of the primary result. The assay generates a qualitative result (positive/negative) based on spectrophotometric measurements. The phrase "qualitative analysis" refers to the output of the device.

7. The Type of Ground Truth Used (expert consensus, pathology, outcomes data, etc.)

• Type of Ground Truth:
  • For the comparative study assessing agreement, the Emit® II Propoxyphene assay (predicate device) was used as a reference for initial comparison.
  • For resolving discrepancies and confirming concentrations, GC/MS (Gas Chromatography/Mass Spectrometry) was used, which is considered the "gold standard" confirmatory method for drug testing.

8. The Sample Size for the Training Set

• Sample Size for Training Set: Not applicable/not provided. This document describes the performance of a developed assay for regulatory submission, not the development process involving a separate training set for a machine learning model. Immunoassays are not "trained" in the machine learning sense; rather, they are designed and optimized based on chemical and biological principles.

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

• Ground Truth for Training Set: Not applicable. As mentioned above, this is an immunoassay, not a machine learning model, so there isn't a "training set" with ground truth in the AI context. The assay's parameters would have been optimized through laboratory experimentation and validation, rather than learning from a labeled training dataset.

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