(75 days)
The COC Flex® reagent cartridge used on the Dimension® clinical chemistry system provides reagents for an in vitro diagnostic test intended for the qualitative and semi-quantitative determination of benzoylecgonine (cocaine metabolite) in human urine using a cutoff of 150 or 300 ng/mL. Measurements obtained with the COC method are used in the diagnosis and treatment of cocaine use or overdose.
The COC method provides only a preliminary analytical test result. A more specific alternate chemical method must be used in order to obtain a confirmed analytical result. Gas chromatography/mass spectrometry (GC/MS) is the preferred confirmatory method. Other chemical confirmation methods are available. Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.
The Dade Behring Dimension® COC method is an in vitro diagnostic device that consists of prepackaged reagents in a plastic cartridge (Flex®) for use on the Dade Behring Dimension® clinical chemistry system.
Here's an analysis of the provided text regarding the acceptance criteria and study for the Dimension® Urine Cocaine Metabolite Screen (COC) Flex® reagent cartridge:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (Implied) | Reported Device Performance (COC Flex® vs. Predicate) | Reported Device Performance (COC Flex® vs. GC/MS) |
|---|---|---|
| Correct identification of positive samples (relative to predicate) | 69 true positives | 66 true positives |
| Correct identification of negative samples (relative to predicate) | 52 true negatives | 51 true negatives |
| Minimize false positives (relative to predicate) | 2 false positives | 5 false positives |
| Minimize false negatives (relative to predicate) | 2 false negatives | 3 false negatives |
| "Near-cutoff samples" performance | All discrepant results were within +/- 25% of the cutoff when compared to GC/MS. | All discrepant results were within +/- 25% of the cutoff when compared to GC/MS. |
Note: The document does not explicitly state quantitative acceptance criteria (e.g., "sensitivity must be >95%"). Instead, it presents the results of method comparison studies against a predicate device and a reference method (GC/MS). The implied acceptance criteria are that the device performs comparably to the predicate and is reasonably accurate when compared to GC/MS, especially around the cutoff.
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Size (vs. Predicate):
- Positive: 69 + 2 = 71
- Negative: 2 + 52 = 54
- Total: 125 samples
- Test Set Size (vs. GC/MS):
- Positive: 66 + 3 = 69
- Negative: 5 + 51 = 56
- Total: 125 samples
- Data Provenance: Not explicitly stated. The document indicates it's a 510(k) submission, typically implying data is gathered from laboratory studies. It does not specify country of origin or whether it's retrospective or prospective.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications
- Not applicable. This device is an in vitro diagnostic (IVD) based on chemical analysis, not interpretation by human experts. The ground truth is established by chemical reference methods.
4. Adjudication Method for the Test Set
- Not applicable. Human adjudication is not relevant for this type of IVD device. The comparison is made against a reference method (GC/MS) or a predicate device. Discrepancies are usually investigated by re-testing or confirmation with the higher-order reference method. The document notes that discrepant specimens were further analyzed by GC/MS.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No. This is an in vitro diagnostic device for chemical analysis of urine samples. MRMC studies are typically used for medical imaging devices where human readers interpret results.
6. Standalone Performance
- Yes. The data presented directly reflects the "standalone" performance of the Dimension® Urine Cocaine Metabolite Screen (COC) Flex® reagent cartridge. The method comparison table shows the agreement/disagreement of the device with the predicate (Syva® Emit® II Plus) and with the gold standard (GC/MS). Its performance is evaluated purely on its analytical results without human interpretation in the comparison.
7. Type of Ground Truth Used
- Chemical Reference Method (GC/MS): For the critical evaluation of performance, Gas Chromatography/Mass Spectrometry (GC/MS) was used as the confirmatory method for benzoylecgonine levels. This is explicitly stated in the Indications for Use and in the "Discrepant specimens" section. The predicate device (Syva® Emit® II Plus) also served as a comparative reference.
8. Sample Size for the Training Set
- Not reported/applicable. This document describes a 510(k) submission for an in vitro diagnostic assay, which is a chemical reagent-based test. These types of assays typically do not involve "training sets" in the machine learning sense. Their performance characteristics are established through analytical validation studies (e.g., linearity, precision, interference, method comparison) using samples with known analyte concentrations or clinical samples characterized by reference methods. The provided document details the method comparison study results, which are performance data, not training data.
9. How the Ground Truth for the Training Set Was Established
- Not reported/applicable. As mentioned above, a training set as understood in AI/machine learning is not relevant for this device. The development of such chemical assays relies on established analytical chemistry principles and calibrators to define thresholds and ensure accurate measurement.
§ 862.3250 Cocaine and cocaine metabolite test system.
(a)
Identification. A cocaine and cocaine metabolite test system is a device intended to measure cocaine and a cocaine metabolite (benzoylecgonine) in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of cocaine use or overdose.(b)
Classification. Class II (special controls). A cocaine and cocaine metabolite 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).