(80 days)
The LZI Oxycodone Enzyme Immunoassay is intended for the qualitative and semiquantitative determination of Oxycodone in human urine at the cutoff values of 100 and 300 ng/mL. The assay is designed for professional 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 Oxycodone Drugs of Abuse (DAU) Calibrators are for use as calibrators in the qualitative and semi-quantitative calibration of the LZI Oxycodone Enzyme Immunoassay.
The LZI Oxycodone Drugs of Abuse (DAU) Controls are for use as assayed quality control materials to monitor the precision of the LZI Oxycodone Enzyme Immunoassay.
The assay provides only a preliminary analytical result. A more specific alternative chemical method 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 Oxycodone assay is a homogeneous enzyme immunoassay with ready-to-use liquid reagents. 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, oxycodone-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 oxycodone-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 Oxycodone Enzyme Immunoassay is a kit comprised of two reagents, an R1 and R2, which are bottled separately but sold together within the kit.
The R. solution contains mouse monoclonal anti-Oxycodone antibody, glucose-6-phosphate (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 oxycodone in buffer with sodium azide (0.09%) as preservative.
The LZI Oxycodone Enzyme Immunoassay (K050733) calibrators and controls designated for use at the 100 and 300 ng/mL cutoffs contain 0, 50, 75, 100, 125, 225, 300, 375, 500, and 800 ng/mL of oxycodone in human urine with sodium azide (0.09%) as preservative. These six calibrators and four controls are sold as individual bottles.
The provided text describes the LZI Oxycodone Enzyme Immunoassay, its intended use, and its performance characteristics. Here's a breakdown of the requested information:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state formal "acceptance criteria" for the performance studies in the way one might see in a pre-defined validation plan. However, it presents the reported performance characteristics which implicitly serve as the achieved benchmarks.
| Performance Characteristic | Acceptance Criteria (Implied by Study Design) | Reported Device Performance |
|---|---|---|
| Precision (100 ng/mL Cutoff) | Expected to correctly classify positive and negative samples at various concentrations around the cutoff. Minor variability at the cutoff is acceptable. | Semi-Quantitative: At 100 ng/mL cutoff, 39 Pos/49 Neg results out of 88 total determinations. |
| Qualitative: At 100 ng/mL cutoff, 25 Pos/63 Neg results out of 88 total determinations. | ||
| Samples significantly below the cutoff: 88 Negative. | ||
| Samples significantly above the cutoff: 88 Positive. | ||
| Precision (300 ng/mL Cutoff) | Expected to correctly classify positive and negative samples at various concentrations around the cutoff. Minor variability at the cutoff is acceptable. | Semi-Quantitative: At 300 ng/mL cutoff, 26 Pos/62 Neg results out of 88 total determinations. |
| Qualitative: At 300 ng/mL cutoff, 23 Pos/65 Neg results out of 88 total determinations. | ||
| Samples significantly below the cutoff: 88 Negative. | ||
| Samples significantly above the cutoff: 88 Positive. | ||
| Linearity (100 & 300 ng/mL Cutoff) | High correlation between measured and target values across the dynamic range. | y = 0.974x + 1.4518, r² = 0.998 for 0-800 ng/mL. |
| Method Comparison (100 ng/mL Cutoff) | High agreement with a confirmatory method (GC/MS or LC/MS) for clinical samples. | 93.75% agreement with positive, 100.0% agreement with negative samples (out of 89 samples). |
| Method Comparison (300 ng/mL Cutoff) | High agreement with a confirmatory method (GC/MS or LC/MS) for clinical samples. | 96.1% agreement with positive, 98.0% agreement with negative samples (out of 101 samples). |
| Endogenous Compound Interference & Specificity & Cross-Reactivity | No significant undesired interference. | No significant undesired cross-reactants or endogenous substance interference was observed. |
2. Sample Size Used for the Test Set and the Data Provenance
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Precision Studies (Test Set for Precision):
- For both 100 ng/mL and 300 ng/mL cutoffs, and for both semi-quantitative and qualitative results:
- Sample Size: 88 determinations per concentration level. This was derived from "Within Run" (22 determinations) multiplied by the number of runs (not explicitly stated, but implied to be 4 runs for "Total Precision" as 22 * 4 = 88). There were 9 concentration levels tested for each cutoff.
- Data Provenance: The document does not explicitly state the country of origin. The samples used for precision appear to be contrived samples at specific concentrations rather than clinical samples, as they are described as "Sample Concentration" in ng/mL. Therefore, they are laboratory-prepared samples. The study is prospective in nature as it's a performance validation for a new device.
- For both 100 ng/mL and 300 ng/mL cutoffs, and for both semi-quantitative and qualitative results:
-
Method Comparison - Clinical Samples (Test Set for Method Comparison):
- 100 ng/mL Cutoff:
- Sample Size: 89 clinical unaltered samples.
- Data Provenance: The document does not explicitly state the country of origin. These are "clinical unaltered samples," suggesting they were collected from patients. The study would be considered retrospective if these samples were pre-collected, or prospective if collected specifically for the study. The document does not specify.
- 300 ng/mL Cutoff:
- Sample Size: 101 clinical unaltered samples.
- Data Provenance: Similar to the 100 ng/mL cutoff, country of origin is not specified, and it's unclear if these were retrospective or prospective clinical samples.
- 100 ng/mL Cutoff:
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
Not applicable in the conventional sense for this type of immunoassay device. The ground truth for the test set was established by:
- For precision studies: The known concentrations of the laboratory-prepared samples.
- For method comparison studies: A "more specific alternative chemical method," specifically Gas or liquid chromatography/mass spectrometry (GC/MS or LC/MS). These are analytical chemistry techniques, not human expert evaluations.
4. Adjudication Method for the Test Set
Not applicable. The ground truth was established by objective analytical methods (known concentrations or GC/MS/LC/MS), not by subjective expert review that would require adjudication.
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 automated immunoassay for drug detection in urine, not an imaging device or AI-assisted diagnostic tool that involves human readers/interpreters in this context. The assay provides a preliminary analytical result, which would then be confirmed by other laboratory methods.
6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was done
Yes, the performance studies described are essentially standalone algorithmic performances. The LZI Oxycodone Enzyme Immunoassay is an automated system run on "automated clinical chemistry analyzers" (e.g., Hitachi 717). The performance metrics (precision, linearity, method comparison) reflect the device's accuracy in autonomously classifying samples or measuring concentrations. There is no explicit "human-in-the-loop" aspect to its primary interpretive function as presented.
7. The Type of Ground Truth Used
- For Precision Studies: Artificially prepared samples with known concentrations of oxycodone.
- For Method Comparison Studies: Confirmatory analytical methods, specifically Gas or liquid chromatography/mass spectrometry (GC/MS or LC/MS). The document states: "A more specific alternative chemical method 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."
8. The Sample Size for the Training Set
The document does not explicitly mention a "training set" in the context of machine learning or AI algorithm development. This device is an immunoassay, which typically relies on chemical reagent interactions rather than data-driven machine learning models that require training sets. The "training" would be the initial development and formulation of the assay reagents and conditions.
9. How the Ground Truth for the Training Set Was Established
As there is no explicit mention of a "training set" for an AI or machine learning algorithm, this question is not directly applicable. The "ground truth" during the development of an immunoassay is based on established principles of analytical chemistry, reagent optimization, and calibration against known standards.
§ 862.3650 Opiate test system.
(a)
Identification. An opiate test system is a device intended to measure any of the addictive narcotic pain-relieving opiate drugs in blood, serum, urine, gastric contents, and saliva. An opiate is any natural or synthetic drug that has morphine-like pharmocological actions. The opiates include drugs such as morphine, morphine glucoronide, heroin, codeine, nalorphine, and meperedine. Measurements obtained by this device are used in the diagnosis and treatment of opiate use or overdose and in monitoring the levels of opiate administration to ensure appropriate therapy.(b)
Classification. Class II (special controls). An opiate test system is not exempt if it is intended for any use other than employment or insurance testing or is intended for Federal drug testing programs. The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9, provided the test system is intended for employment and insurance testing and includes a statement in the labeling that the device is intended solely for use in employment and insurance testing, and does not include devices intended for Federal drug testing programs (e.g., programs run by the Substance Abuse and Mental Health Services Administration (SAMHSA), the Department of Transportation (DOT), and the U.S. military).