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The LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay is intended for the qualitative and semi-quantitative determination of 6-Acetylmorphine in neat human oral fluid, collected into the LZI Oral Fluid Collector, at the cutoff value of 4 ng/mL. The assay is designed for prescription use with a number of automated clinical chemistry analyzers.

The semi-quantitative mode is for purposes of (1) enabling laboratories to determine an appropriate dilution of the specimen for confirmation by a confirmatory method such as GCMS and LCMS or (2) permitting laboratories to establish quality control procedures.

The LZI Oral Fluid 6-Acetylmorphine Calibrators are for use as calibrators in the qualitative and semi-quantitative calibration of the LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay at the cutoff value of 4 ng/mL.

The LZI Oral Fluid 6-Acetylmorphine Controls are for use as assayed quality control materials to monitor the precision of the LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay at the cutoff value of 4 ng/mL.

The assay provides only a preliminary analytical result. A more specific alternative chemical must be used in order to obtain a confirmed analytical result. Gas or liquid chromatography/mass spectrometry (GC/MS or LC/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 test result is positive.

The LZI Oral Fluid 6-Acetylmorphine assay is a homogeneous enzyme immunoassay with ready-to-use liquid reagent. The assay is based on competition between drug in the sample and drug labeled with the enzyme glucose-6-phosphate dehydrogenase (G6PDH) for a fixed amount of antibody in the reagent. Enzyme activity decreases upon binding to the antibody, and the drug concentration in the sample is measured in terms of enzyme activity. In the absence of drug in the sample, 6-Acetylmorphine-labeled G6PDH conjugate is bound to antibody, and the enzyme activity is inhibited. On the other hand, when free drug is present in the sample, antibody would bind to free drug, the unbound 6-Acetylmorphine-labeled G6PDH then exhibits its maximal enzyme activity. Active enzyme converts nicotinamide adenine dinucleotide (NAD) to NADH, resulting in an absorbance change that can be measured spectrophotometrically at 340 nm.

The LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay is a kit comprised of two reagents, an R1 and R2 which are bottled separately but sold together within the kit.

The R1 solution contains mouse monoclonal anti-6-Acetylmorphine antibody, glucose-6phosphate (G6P) nicotinamide adenine dinucleotide (NAD), stabilizers, and sodium azide (0.09%) as a preservative. The R2 solution contains glucose-6-phosphate dehydrogenase (G6PDH) labeled with 6-Acetylmorphine in buffer with sodium azide (0.09%) as preservative.

The LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay calibrators and controls designated for use at the 4 ng/mL cutoffs contain 0, 2, 4, 6, 10, and 20 ng/mL of 6-Acetylmorphine in synthetic oral fluid matrix with sodium azide (0.09%) as preservative. These five calibrators and two controls are sold as individual bottles.

The provided document is a 510(k) premarket notification for the LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay (EIA), its calibrators, and controls. This device is an in-vitro diagnostic test for detecting 6-Acetylmorphine in human oral fluid.

Here's an analysis of the acceptance criteria and the study that proves the device meets them, based on the provided text:

1. A table of acceptance criteria and the reported device performance

The document does not explicitly state "acceptance criteria" in a separate section with numerical thresholds for performance metrics. Instead, it presents performance characteristic studies (Precision, Analytical Recovery, Method Comparison), and the results of these studies implicitly demonstrate the device's acceptable performance for determining substantial equivalence to a predicate device. The primary performance characteristic related to diagnostic accuracy is the Method Comparison with clinical samples.

Here's a table summarizing the reported device performance, particularly focusing on the "Method Comparison" results, as this is the most direct measure of accuracy against a reference method:

2. Sample size used for the test set and the data provenance

• Test Set Sample Size: 150 clinical unaltered samples were used for the Method Comparison study (clinical samples).
• Data Provenance: Not explicitly stated (e.g., country of origin, retrospective/prospective). It is referred to as "clinical unaltered samples," suggesting real-world specimens, but further details are not provided in the summary.

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

The ground truth for the test set in the Method Comparison study was established by Gas Chromatography/Mass Spectrometry (GC/MS) analysis. This is a laboratory analytical method, not a human expert interpretation. Therefore, the concept of "experts" and their qualifications as typically applied in image analysis or clinical diagnosis scenarios (e.g., radiologists) does not directly apply here. The GC/MS method itself is the "gold standard" or reference method for confirmation.

4. Adjudication method for the test set

Not applicable. Since the ground truth was established by GC/MS, an objective chemical analysis, there was no need for human expert adjudication. The immunoassay results were directly compared to the GC/MS results.

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

Not applicable. This device is an in-vitro diagnostic assay (an enzyme immunoassay) and does not involve human readers interpreting images or data that would be assisted by AI. The comparison is between the immunoassay's analytical result and a confirmatory chemical method (GC/MS).

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

Yes, in a sense. The LZI Oral Fluid 6-Acetylmorphine Enzyme Immunoassay operates as a standalone analytical device. Its performance is measured independently of a human interpreter's input, generating a preliminary analytical result (positive/negative or semi-quantitative concentration). The "human-in-the-loop" aspect comes after this preliminary result, where a more specific method (like GC/MS) is recommended for confirmation, and clinical judgment is required.

7. The type of ground truth used

The ground truth used for the Method Comparison (clinical samples) was Gas Chromatography/Mass Spectrometry (GC/MS) analysis. This is described as the "preferred confirmatory method" and the "independent analytical method" for establishing substantial equivalence.

8. The sample size for the training set

This document describes a premarket notification for an in-vitro diagnostic device, not a machine learning or AI algorithm. Therefore, the concept of a "training set" in the context of AI models does not apply directly. The development of the immunoassay itself would have involved internal validation and optimization, but specific "training set" sizes are not reported in this regulatory submission.

9. How the ground truth for the training set was established

As explained above, the concept of a "training set" as understood for AI/ML devices is not applicable here. The immunoassay is a biochemical reaction-based test. Its development is based on established principles of immunology and enzyme kinetics, and its performance characteristics are demonstrated through analytical and clinical validation studies as detailed in the document (precision, recovery, method comparison to GC/MS). Ground truth for these internal development and validation steps would also have relied on reference analytical methods like GC/MS or gravimetric preparation of known concentration samples.

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