(53 days)
The Creatinine assay is used for the quantitation of creatinine in human serum, plasma, or urine. Creatinine measurements are used in the diagnosis and treatment of renal diseases and in monitoring renal dialysis.
Creatinine is an in vitro diagnostic assay for the quantitative determination of creatinine in human serum, plasma, or urine. The Creatinine assay is a clinical chemistry assay in which the creatinine in the sample, at an alkaline pH, reacts with picrate to form a creatinine-picrate complex. The rate of increase in absorbance at 500 nm due to the formation of this complex is directly proportional to the amount of creatinine in the sample.
Here's a breakdown of the acceptance criteria and study details for the Creatinine assay based on the provided 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
The device is a laboratory assay, so acceptance criteria are related to analytical performance characteristics compared to predicate devices, rather than clinical endpoints. The acceptance criteria are implied by the claim of "substantially equivalent" performance to the predicate devices. The key performance metrics are correlation, precision, linearity, and sensitivity (limit of quantitation).
| Performance Metric | Acceptance Criteria (Implied by Predicate Performance) | Reported Device Performance (Creatinine Assay) | Comments |
|---|---|---|---|
| Method Comparison (Serum) | Acceptable correlation with Roche Cobas Mira Plus Creatinine assay | Correlation Coefficient: 0.9993 | |
| Slope: 0.980 | |||
| Y-intercept: -0.150 mg/dL | Demonstrated strong linear correlation. | ||
| Method Comparison (Urine) | Acceptable correlation with Boehringer Mannheim Creatinine assay on Hitachi 717 Analyzer | Correlation Coefficient: 0.9995 | |
| Slope: 1.060 | |||
| Y-intercept: 4.637 mg/dL | Demonstrated strong linear correlation. | ||
| Precision (Serum) | Acceptable (compared to predicate or established clinical standards) | Level 1/Panel 111 Total %CV: 4.5% | |
| Level 2/Panel 112 Total %CV: 2.2% | Within acceptable analytical variability. | ||
| Precision (Urine) | Acceptable (compared to predicate or established clinical standards) | Level 1/Panel 131 Total %CV: 2.1% | |
| Level 2/Panel 132 Total %CV: 2.5% | Within acceptable analytical variability. | ||
| Linearity | Up to a certain clinically relevant concentration | Up to 42 mg/dL | Covers a broad range of creatinine concentrations. |
| Limit of Quantitation (Sensitivity) | Below a clinically relevant threshold | 0.3 mg/dL | Indicates good sensitivity for low creatinine levels. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size for Test Set: Not explicitly stated for either the method comparison or precision studies. The document only mentions "Comparative performance studies were conducted" and "Precision studies were conducted using the Creatinine assay. Within-run, between-run, and between-day studies were performed using two levels of control material."
- Data Provenance: Not explicitly stated (e.g., country of origin). The studies appear to be prospective as they were conducted specifically for the 510(k) submission, comparing the new device against predicate devices and evaluating its performance characteristics.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
- This is a quantitative in vitro diagnostic assay. The "ground truth" for the test set is established by the measurements obtained from the predicate devices (Roche Cobas Mira Plus Creatinine assay for serum, and Boehringer Mannheim Creatinine assay on Hitachi 717 Analyzer for urine). No human experts were involved in establishing the "ground truth" for the numerical values. The validity of these predicate devices' measurements is assumed.
4. Adjudication Method for the Test Set
- Not applicable. This is not a study requiring human adjudication or consensus on interpretations. The comparison is objective (numerical assays).
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, Effect Size
- No, a multi-reader multi-case (MRMC) comparative effectiveness study was not done. This type of study is typically for imaging devices where human interpretation plays a significant role. This is a quantitative chemical assay.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
- Yes, this study is inherently a standalone performance evaluation of the Creatinine assay device. The performance characteristics (correlation, precision, linearity, sensitivity) are assessed for the device itself, without human intervention in the measurement process (beyond standard lab operation).
7. The Type of Ground Truth Used
- The "ground truth" for evaluating the Creatinine assay's performance is the measurements provided by legally marketed and accepted predicate devices (Roche Cobas Mira Plus Creatinine assay for serum and Boehringer Mannheim Creatinine assay for urine), along with established analytical performance metrics (precision, linearity, sensitivity).
8. The Sample Size for the Training Set
- Not applicable / Not stated. This is an in vitro diagnostic assay, not a machine learning algorithm that requires a "training set" in the conventional sense. The "training" for such a device involves chemical and engineering optimization during development, not data-driven model training.
9. How the Ground Truth for the Training Set was Established
- Not applicable. As mentioned above, it's not a machine learning model requiring a training set with established ground truth. The "ground truth" in the context of developing such an assay would relate to physicochemical principles and analytical accuracy established through laboratory standards and controls.
§ 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.