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The Barbiturate Enzyme Immunoassay is a homogeneous enzyme immunoassay with a 200 ng/mL and/or 300 ng/mL cutoffs. The assay is intended for use in the qualitative and semiquantitative analyses of barbiturates in human urine. The assay is designed for professional use with a number of automated clinical chemistry analyzers.

Measurements obtained by this device are used in the diagnosis and treatment of barbiturate use or overdose and in monitoring levels of barbiturate to ensure appropriate therapy.

The Barbiturate 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 judgment should be applied to any drug-ofabuse test result, particularly when preliminary positive results are used.

The Barbiturate Drug of Abuse Calibrators are intended for in vitro diagnostic use for the calibration of the Barbiturate Enzyme Immunoassay to detect barbiturates in human urine.

The Barbiturate Drug of Abuse Controls are intended for in vitro diagnostic use for the validation of the Barbiturate Enzyme Immunoassay to detect barbiturates in human urine.

Device Description

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

The assay is based on competition between barbiturate 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 G6PDH enzyme causing a decrease in enzyme activity. It is therefore the drug concentration is proportional to the enzyme activity. The G6PDH enzyme activity is determined spectrophotometrically at 340 nm by measuring its ability to covert nicotinamide adenine dinucleotide (NAD) to NADH.

All of the Single Analyte Urine DAU Calibrators and Controls are human urine-based liquid, and ready to use. These Calibrators and Controls do not have any especially unique technical characteristics. Each contains a known concentration of a specific drug analyte.

The Negative DAU calibrator is a processed, drug-free human urine matrix, which has also been used with all assays. The calibrators and controls are prepared by spiking known concentrations of drug analyte into the Negative DAU Calibrator matrix.

AI/ML Overview

Here's a breakdown of the acceptance criteria and the study information for the Lin-Zhi International, Inc. Barbiturate Enzyme Immunoassay, based on the provided text:

1. Table of Acceptance Criteria and Reported Device Performance:

The document primarily focuses on demonstrating substantial equivalence to a predicate device rather than explicitly stating pre-defined acceptance criteria with specific thresholds for each performance metric. However, we can infer the acceptance criteria for the LZI device by comparing its performance to that of the predicate device (Syva EMIT® II Plus Barbiturate Assay). The goal is to show comparable or acceptable performance.

Feature	Predicate Device (SYVA's Barbiturate EIA) Reported Performance	LZI's Barbiturate EIA Reported Performance	Inferred Acceptance Criteria/Comparison
Precision
Within Run Qualitative (mAbs/min %CV)	Negative: 0.4%150 ng/mL: 0.4%200 ng/mL: 0.5%225 ng/mL: 0.4%250 ng/mL: 0.4%300 ng/mL: 0.5%375 ng/mL: 0.4%	Negative: 0.8%100 ng/mL: 0.6%200 ng/mL: 1.1%300 ng/mL: 0.1%400 ng/mL: 0.7%1000 ng/mL: 0.6%	Comparable %CV to predicate; generally low %CVs (e.g., <5%). LZI's values are mostly in the same low range.
Within Run Semi-quantitative (ng/mL %CV)	150 ng/mL: 3.8%200 ng/mL: 1.8%225 ng/mL: 1.5%250 ng/mL: 1.4%300 ng/mL: 1.3%375 ng/mL: 1.0%	100 ng/mL: 4.8%200 ng/mL: 3.8%300 ng/mL: 2.8%400 ng/mL: 3.6%	Comparable %CV to predicate; generally low %CVs (e.g., <5%). LZI's values are mostly in the same low range.
Run-To-Run Qualitative (mAbs/min %CV)	Negative: 0.6%150 ng/mL: 0.6%200 ng/mL: 0.6%225 ng/mL: 0.6%250 ng/mL: 0.6%300 ng/mL: 0.6%375 ng/mL: 0.7%	Negative: 0.8%100 ng/mL: 0.7%200 ng/mL: 0.5%300 ng/mL: 0.4%400 ng/mL: 0.4%1000 ng/mL: 0.4%	Comparable %CV to predicate; generally low %CVs (e.g., <5%). LZI's values are mostly in the same low range.
Run-To-Run Semi-quantitative (ng/mL %CV)	150 ng/mL: 4.2%200 ng/mL: 2.4%225 ng/mL: 1.9%250 ng/mL: 2.4%300 ng/mL: 2.1%375 ng/mL: 1.9%	100 ng/mL: 3.1%200 ng/mL: 4.9%300 ng/mL: 4.8%400 ng/mL: 3.3%	Comparable %CV to predicate; generally low %CVs (e.g., <5%). LZI's values are mostly in the same low range.
Sensitivity	20 ng/mL	25 ng/mL	Similar sensitivity to the predicate device.
Accuracy	Vs. a commercial EIA: 95.6% agreement (positive), 99% agreement (negative)	Vs. Syva (n=105): 91.1% agreement (positive), 100% agreement (negative)	High agreement with predicate device (syva). "100% vs. GC/MS /HPLC" for positive samples is a key benchmark.
Analytical Recovery	Qualitative: 100% accuracy on positive vs. negative testsSemi-quantitative: Quantitates within ±15% of nominal concentration between 40 ng/mL and 900 ng/mL	Qualitative: 100% accuracy on positive vs. negative testsSemi-quantitative: Quantitates within ±15% of nominal concentration between 40 ng/mL and 800 ng/mL	Both qualitative and semi-quantitative recovery consistent with industry standards and predicate device.
Specificity	See attached Syva's Barbiturate Assay package insert	Comparable to the predicate device.	Specificity should be comparable to the predicate, implying minimal cross-reactivity to common drugs.

Study Proving Device Meets Acceptance Criteria:

The provided document describes a study comparing the Lin-Zhi International (LZI) Barbiturate Enzyme Immunoassay to a legally marketed predicate device, the Syva EMIT® II Plus Barbiturate Assay (K010934). The studies evaluated precision, sensitivity, accuracy, analytical recovery, and specificity. The conclusion states: "All the studies showed acceptable results when compared to the predicate device."

Summary of Study Information:

Sample size used for the test set and the data provenance:
- Test Set Size: For accuracy, the test set size was n=105 samples against the Syva predicate device. Specific sample sizes for precision studies (e.g., number of replicates for within-run and run-to-run) are not explicitly stated, but the tables show "Mean," "SD," and "%CV" which implies multiple measurements.
- Data Provenance: Not explicitly stated (e.g., country of origin). The document implies the tests were conducted by Lin-Zhi International, Inc.
- Retrospective or Prospective: Not explicitly stated, though performance characteristic studies like these are typically conducted prospectively with defined protocols.
Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- For accuracy, the LZI device was compared against the Syva predicate and also against GC/MS (Gas Chromatography/Mass Spectrometry) / HPLC (High-Performance Liquid Chromatography) for positive samples, where it showed 100% agreement. GC/MS is considered the "preferred confirmatory method" and generally serves as the gold standard / ground truth for drug detection. The number of experts interpreting these GC/MS/HPLC results is not specified, nor are their qualifications. For in-vitro diagnostic devices, the analytical methods themselves establish the ground truth, rather than human experts in the traditional sense, though lab personnel operating these instruments would be qualified.
Adjudication method for the test set:
- Not applicable as this is an in-vitro diagnostic device. Analytical results are compared quantitatively, not through expert adjudication of images or clinical assessments.
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 study was not done. This device is an in-vitro diagnostic immunoassay, not an AI-powered diagnostic imaging or decision support tool that involves human "readers" or AI assistance.
If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Yes, a standalone performance study was done. The entire "Performance Characteristics" section details the analytical performance of the LZI Barbiturate Enzyme Immunoassay as a standalone device. The device itself (the immunoassay) produces quantitative or qualitative results. Human interpretation is primarily for clinical context, but the analytical performance is intrinsic to the device.
The type of ground truth used:
- For accuracy, the ground truth was established by Gas Chromatography/Mass Spectrometry (GC/MS) / High-Performance Liquid Chromatography (HPLC) for positive samples, and comparison to the predicate device's performance for overall agreement. These are highly specific and sensitive analytical methods considered definitive for drug identification and quantification.
The sample size for the training set:
- This document describes a pre-market notification for an immunoassay, which typically does not involve "training sets" in the context of machine learning. The assay's parameters (e.g., antibody binding, enzyme conjugates, cutoff values) are developed through R&D and optimized, but a distinct "training set" of samples as used in AI/ML is not directly applicable or described. Calibration is performed using known concentrations of secobarbital, but this is for assay operation, not "training" an algorithm.
How the ground truth for the training set was established:
- As noted above, a "training set" as defined for AI/ML is not applicable. The ground truth for calibration standards and controls (which are analogous to the known inputs) for the calibrators and controls used in the LZI Barbiturate EIA are based on known concentrations of secobarbital spiked into a urine matrix. The nominal concentrations are described as "determined and confirmed by GC/MS" (mentioned for the calibrators and controls product).

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