(65 days)
The ECRE method is an in vitro diagnostic test for the quantitative measurement of creatinine in human serum, plasma, and urine on the Dimension® clinical chemistry system. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis, and as a calculation basis for other urine analytes.
The Dimension® ECRE Flex® reagent cartridge is a prepackaged in-vitro diagnostic test method that is specifically designed to be used on the Dade Behring Dimension® Clinical Chemistry System. The reagents contained in the Dimension® ECRE Flex® reagent cartridge are: Reagent 1 - TAPS buffer, creatinase, sarcosine oxidase, HTIB; Reagent 2 - TAPS buffer, creatininase, horseradish peroxidase, 4-aminophenazon, and potassium hexacyanoferrate (II).
Here's a breakdown of the acceptance criteria and study information for the Dimension® Enzymatic Creatinine (ECRE) Flex® Reagent Cartridge (DF270), based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't explicitly list "acceptance criteria" in a quantitative sense as distinct thresholds that were met. Instead, it focuses on demonstrating substantial equivalence to a predicate device. The performance is assessed through comparative testing with the predicate device.
However, based on the comparative table and the assertion of "substantial equivalent performance," we can infer the targeted performance characteristics by looking at the predicate device's typical performance (which is not detailed here beyond the measuring range) and the new device's reported characteristics.
| Feature | Acceptance Criteria (Inferred from Predicate/Equivalence) | Reported Device Performance (Dimension® ECRE Flex®) |
|---|---|---|
| Intended Use | Quantitative measurement of creatinine for diagnosis/treatment of renal diseases, monitoring dialysis, and as a calculation basis for other urine analytes. | Quantitative measurement of creatinine for diagnosis/treatment of renal diseases, monitoring dialysis, and as a calculation basis for other urine analytes. |
| Sample Type | Human serum, plasma, and urine. | Plasma, serum, and urine. |
| Measuring Range | 0.03 - 30 mg/dL | 0.03 - 20.00 mg/dL |
| Sample Size | 6 µL | 6 µL |
| Measurement Type | Bichromatic end point | Bichromatic end point |
Note: The measuring range of the new device (0.03 - 20.00 mg/dL) is narrower than the predicate (0.03 - 30 mg/dL). While this might typically be a point of divergence, the FDA's clearance implies that this difference was considered acceptable for substantial equivalence, perhaps because the narrower range is still clinically acceptable or covers the vast majority of relevant clinical values, and no specific acceptance criteria for the range were provided. The document states a "comparison of the important similarities and differences" and concludes "substantial equivalent performance."
2. Sample size used for the test set and the data provenance:
- Sample Size for the Test Set: Not explicitly stated. The document mentions "Comparative testing described in the protocol included in this submission," but doesn't provide the number of samples or subjects used in this testing.
- Data Provenance: Not explicitly stated (e.g., country of origin). The document provides no information about whether the data was retrospective or prospective.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
This information is not provided in the document. For in-vitro diagnostic devices like this, "ground truth" is typically established by reference methods or established clinical laboratory practices, not by expert consensus in the way it might be for image analysis or clinical assessments. The comparison is made against the predicate device, implying that the predicate's performance serves as the benchmark.
4. Adjudication method for the test set:
This information is not provided. Given the nature of a chemical assay, adjudication by multiple experts is not a standard practice for establishing a single "ground truth" value for creatinine concentration. The performance is likely assessed by comparing results directly against a reference method or the predicate device.
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:
This is not applicable to this device. An MRMC study is relevant for AI systems that assist human readers in tasks like image interpretation. The Dimension® ECRE Flex® Reagent Cartridge is an in-vitro diagnostic (IVD) assay designed to directly measure a chemical analyte (creatinine) in biological samples, not to assist human readers in interpretation.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
This is not applicable in the context of an IVD reagent cartridge. The "algorithm" here is the chemical reaction and measurement process performed by the Dimension clinical chemistry system using the reagent. The performance of the system (reagent + instrument) is inherently standalone in that it provides a quantitative result directly without human interpretation influencing the measurement itself.
7. The type of ground truth used:
The "ground truth" for evaluating this device would implicitly be results obtained from a legally marketed predicate device (Roche's Creatinine Plus Reagent) or a recognized reference method for creatinine measurement. The document states: "Comparative testing described in the protocol included in this submission demonstrates substantial equivalent performance [to the predicate]."
8. The sample size for the training set:
This information is not provided. For a chemical reagent, the "training set" concept is not analogous to machine learning. Instead, the reagent formulation and assay parameters are developed and optimized through extensive R&D and analytical validation experiments. The document does not detail the number of samples used in this development and optimization phase.
9. How the ground truth for the training set was established:
This information is not provided. Similar to point 8, the concept of "ground truth" for a training set in the context of an IVD reagent typically relates to the accuracy and precision established during the development and optimization phase, often by running samples with known creatinine concentrations (e.g., NIST traceable standards, patient samples quantified by a gold-standard reference method). The document does not describe these specific procedures.
§ 862.1225 Creatinine test system.
(a)
Identification. A creatinine test system is a device intended to measure creatinine levels in plasma and urine. Creatinine measurements are used in the diagnosis and treatment of renal diseases, in monitoring renal dialysis, and as a calculation basis for measuring other urine analytes.(b)
Classification. Class II.