(51 days)
Abuscreen ONLINE for Propoxyphene is an in vitro diagnostic test for the qualitative and semiquantitative detection of propoxyphene and its metabolites in human urine on automated clinical chemistry analyzers at a cutoff concentration of 300 ng/mL. Semiquantitative test results may be obtained that permit laboratories to assess assay performance as part of a quality control program. Measurements obtained by this device are used in the diagnosis of propoxyphene use or abuse.
The proposed Abuscreen ONLINE Propoxyphene test kit is specifically intended for use on the Hitachi 917 Analyzer and future similar analyzer models. It was adapted from the currently marketed Abuscreen ONLINE Propoxyphene test kit. The labeling and packaging have been changed for use on the Hitachi 917 Analyzer as well as an addition of a surfactant to the diluent. This modified test kit is not a replacement to the currently marketed kit.
The Hitachi 917 Analyzer System is a fully automatic, computer-controlled system for clinical chemistry. It was conceived for both quantitative and qualitative in vitro determination using a large variety of tests for analysis, e.g. in serum and urine. Integrated in the system is an ion-selective unit for determination of electrolytes. The throughput per hour is 800 tests for clinical chemistry (1200 with electrolytes). The system consists of the analyzer which performs all functions required for fully automatic sample and test processing. Beginning with the automatic recording of patient samples - provided that they are supplied in barcode-labeled vessels - up to the photometric measurement and results transmission to the computer unit.
Here's an analysis of the acceptance criteria and supporting study for the Abuscreen ONLINE® Propoxyphene device, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the Abuscreen ONLINE® Propoxyphene device can be inferred by comparing its performance to that of its legally marketed predicate device (K945195). The study demonstrates that the new device performs equivalently to the predicate.
| Performance Characteristic | Acceptance Criteria (Implied by Predicate) | Reported Device Performance (Proposed Device) |
|---|---|---|
| Precision Qualitative | >95% negative at 240 ng/mL |
95% positive at 360 ng/mL | >95% negative at 225 ng/mL
95% positive at 375 ng/mL |
| Precision Quantitative (Within Run) | Representative values from K945195:
200 ng/mL: 208 ng/mL (3% CV)
250 ng/mL: 262 ng/mL (2% CV)
300 ng/mL: 292 ng/mL (1% CV)
340 ng/mL: 329 ng/mL (1% CV) | 150 ng/mL: 153 ng/mL (2.0% CV)
225 ng/mL: 239 ng/mL (1.3% CV)
300 ng/mL: 306 ng/mL (1.6% CV)
375 ng/mL: 440 ng/mL (1.0% CV)
450 ng/mL: 473 ng/mL (0.6% CV) |
| Precision Quantitative (Day-to-Day) | Representative values from K945195:
200 ng/mL: 208 ng/mL (3% CV)
250 ng/mL: 262 ng/mL (2% CV)
300 ng/mL: 293 ng/mL (1% CV)
340 ng/mL: 331 ng/mL (1% CV) | 150 ng/mL: 147 ng/mL (5.2% CV)
225 ng/mL: 236 ng/mL (3.1% CV)
300 ng/mL: 302 ng/mL (2.4% CV)
375 ng/mL: 435 ng/mL (2.4% CV)
450 ng/mL: 467 ng/mL (1.2% CV) |
| Accuracy (300 ng/mL Cutoff) | N= 63 Confirmed Pos.
63 Pos.
0 Neg. | N= 50 Confirmed Pos.
50 Pos.
0 Neg. |
| Limit of Detection | 30 ng/mL | 0 ng/mL |
Study Proving Device Meets Acceptance Criteria:
The study described is a non-clinical evaluation comparing the "Abuscreen ONLINE Propoxyphene for Hitachi 917" (the proposed device) against the "Abuscreen ONLINE Propoxyphene (1000 Test Kit)" (the predicate device, K945195). The study aims to demonstrate substantial equivalence based on performance characteristics.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Qualitative Precision: The document states that for the qualitative precision at 300 ng/mL cutoff, the proposed device showed:
- ">95% negative at 225 ng/mL" and ">95% positive at 375 ng/mL". This implies multiple samples were tested at these concentrations to achieve statistical significance for the percentages reported, but the exact number of individual samples is not explicitly given.
- Sample Size for Quantitative Precision: The within-run and day-to-day precision data are presented as Mean (OD) and CV% for Optical Density (OD) values and Mean (ng/mL) and CV% for concentration values at various propoxyphene levels (150, 225, 300, 375, 450 ng/mL). The number of replicates or runs to calculate these means and CVs is not explicitly stated.
- Sample Size for Accuracy:
- Proposed device: N= 50 Confirmed Pos. (meaning 50 samples with confirmed positive results were tested).
- Data Provenance: Not explicitly stated. Given the context of a 510(k) submission from Roche Diagnostic Systems, Inc. in New Jersey, USA, it's highly probable the data was generated in the United States, likely in a laboratory setting or using banked samples. The study is retrospective in the sense that it evaluates the performance of the developed device against established predicate performance.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- Not Applicable: This type of device (in vitro diagnostic for drug detection) does not typically involve expert review of images or clinical assessments to establish ground truth in the same way as, for example, a radiology AI device. The ground truth for such assays is established through analytical methods, often using reference standards or confirmed positive/negative samples.
4. Adjudication Method
- Not Applicable: As mentioned above, this device does not involve human interpretation or subjective assessment that would require an adjudication method. The results are quantitative or qualitative measurements from an automated clinical chemistry analyzer.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No: This is not relevant for this type of in vitro diagnostic device. MRMC studies are typically used for imaging AI devices that assist human readers in tasks like lesion detection or diagnosis. This device provides a direct analytical measurement.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
- Yes: The entire study described focuses on the standalone performance of the "Abuscreen ONLINE Propoxyphene for Hitachi 917" test kit (the proposed device) as an automated assay. It measures its analytical performance characteristics directly, without a human in the diagnostic loop to interpret the results from the device itself. The device directly outputs qualitative or semi-quantitative measurements.
7. Type of Ground Truth Used
- The ground truth for the test set is established by the confirmed concentration of propoxyphene and its metabolites in urine samples. For accuracy, it relies on "Confirmed Pos." samples, implying independent verification of the presence of the drug at or above the cutoff. For precision, it uses samples spiked or prepared to precise known concentrations.
8. Sample Size for the Training Set
- Not explicitly stated: This document describes a 510(k) submission for a new formulation of an existing immunoassay to be run on a specific analyzer. Immunoassays are based on biochemical interactions, not machine learning algorithms that require explicit "training sets" in the computational sense. The "training" for such a device involves optimizing reagent concentrations, reaction conditions, and calibration curves during its development. The text implies the device was "adapted from the currently marketed Abuscreen ONLINE Propoxyphene test kit," suggesting that the underlying assay principles and initial development would have been established previously.
9. How the Ground Truth for the Training Set Was Established
- Not explicitly stated/Not Applicable in the AI/ML sense: As above, this is an immunoassay, not an AI/ML model. The "ground truth" during the development and optimization of such an assay (analogous to a training set) would involve extensive analytical experiments using:
- Reference standards of propoxyphene and its metabolites at known concentrations.
- Characterized positive and negative urine samples.
- Samples with known interfering substances.
- The goal of this "training" phase is to ensure the assay reagents and conditions provide accurate and precise measurements across the intended dynamic range and specificity.
§ 862.3700 Propoxyphene test system.
(a)
Identification. A propoxyphene test system is a device intended to measure propoxyphene, a pain-relieving drug, in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of propoxyphene use or overdose or in monitoring levels of propoxyphene to ensure appropriate therapy.(b)
Classification. Class II (special controls). A propoxyphene 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).