(169 days)
The EXTC Flex® reagent cartridge used on the Dimension® clinical chemistry system provides reagents for an in vitro diagnostic test intended for the qualitative and semiquantitative determination of methylenedioxymethamphetamine (MDMA) and closely related drugs in human urine using a cutoff of either 300 or 500 ng/mL. Measurements obtained with the EXTC method are used in the diagnosis and treatment of ecstasy use or overdose.
The EXTC 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 Dimension® Urine Ecstasy Screen Flex® reagent cartridge is an in vitro diagnostic device that consists of prepackaged reagents in a plastic eight-well cartridge for use on the Dade Behring Dimension® clinical chemistry system.
Acceptance Criteria and Device Performance Study for Dimension® Urine Ecstasy Screen Flex® Reagent Cartridge
This report summarizes the acceptance criteria and the study proving the Dimension® Urine Ecstasy Screen Flex® reagent cartridge meets these criteria, as detailed in the provided 510(k) Premarket Notification (K053337).
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for this device are implicitly tied to demonstrating substantial equivalence to the predicate device (Emit® II Plus Ecstasy Assay, K043028) through method comparison studies against a reference method. The primary measure of performance is the percentage agreement with Gas Chromatography/Mass Spectrometry (GC/MS). While explicit numerical acceptance criteria for percent agreement are not stated, the reported values are presented as evidence of acceptable performance for substantial equivalence.
| Acceptance Criteria (Implicit) | Reported Device Performance (vs. GC/MS) |
|---|---|
| Demonstrate substantial equivalence to predicate device | |
| Acceptable performance when compared to reference method GC/MS at 300 ng/mL cutoff | 92% agreement (Concordance Table) |
| Acceptable performance when compared to reference method GC/MS at 500 ng/mL cutoff | 91.2% agreement (Concordance Table) |
The device performance is reported as the percent agreement between the EXTC Flex® reagent cartridge and the reference method (GC/MS) at both cutoffs.
2. Sample Size and Data Provenance
The sample sizes for the test set can be derived from the concordance tables:
- 300 ng/mL Cutoff Test Set:
- Positive (GC/MS) samples: 73
- Negative (GC/MS) samples: 54
- Total samples: 73 (positive concordant) + 11 (negative discordant) + 54 (negative concordant) + 0 (positive discordant) = 138 urine samples
- 500 ng/mL Cutoff Test Set:
- Positive (GC/MS) samples: 58
- Negative (GC/MS) samples: 56
- Total samples: 58 (positive concordant) + 11 (negative discordant) + 56 (negative concordant) + 0 (positive discordant) = 125 urine samples
The document does not explicitly state the country of origin of the data or whether it was retrospective or prospective.
3. Number of Experts and Qualifications for Ground Truth
The document does not mention the use of experts to establish ground truth for the test set. Instead, it states that Gas Chromatography/Mass Spectrometry (GC/MS) was used as the reference method to establish the ground truth. GC/MS is a highly sensitive and specific analytical technique considered a definitive method for drug confirmation, acting as the "gold standard" in this context rather than relying on human expert interpretation.
4. Adjudication Method
The document does not describe an adjudication method for the test set. Since the ground truth was established by GC/MS, a highly objective analytical method, a formal adjudication process involving human experts would typically not be required for the primary result.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No MRMC comparative effectiveness study was performed or described in the provided document. The device is a diagnostic reagent cartridge for an automated clinical chemistry system, not a device requiring human interpretation of output. Therefore, the concept of human readers improving with or without AI assistance is not applicable here.
6. Standalone Performance Study
Yes, a standalone performance study was done. The "Method comparison studies were conducted with the EXTC Flex® reagent cartridge on the Dimension® clinical chemistry system vs. a reference method (GC/MS)." This directly assessed the algorithm's performance (as embodied by the reagent cartridge and system) without human intervention in the result determination.
7. Type of Ground Truth Used
The type of ground truth used was analytical reference method (Gas Chromatography/Mass Spectrometry - GC/MS). The document explicitly states: "Method comparison studies were conducted with the EXTC Flex® reagent cartridge on the Dimension® clinical chemistry system vs. a reference method (GC/MS)." and "GC/MS is the preferred confirmatory method."
8. Sample Size for the Training Set
The document does not specify the sample size for the training set. The provided information focuses solely on the performance evaluation against a reference method, which serves as the validation or test set.
9. How the Ground Truth for the Training Set was Established
Since the document does not mention a training set or its sample size, it does not describe how the ground truth for any training set was established. This type of 510(k) submission for an in vitro diagnostic (IVD) often focuses on validation rather than AI/machine learning model training.
§ 862.3100 Amphetamine test system.
(a)
Identification. An amphetamine test system is a device intended to measure amphetamine, a central nervous system stimulating drug, in plasma and urine. Measurements obtained by this device are used in the diagnosis and treatment of amphetamine use or overdose and in monitoring levels of amphetamine to ensure appropriate therapy.(b)
Classification. Class II (special controls). An amphetamine 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).