(106 days)
A creatinine test system is a device intended to measure creatinine levels in serum, 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.
Creatinine is an in vitro diagnostic assay for the quantitative analysis of creatinine in human serum, plasma, or urine. At an alkaline pH, creatinine in the sample reacts with picrate in the reagent 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 concentration of creatinine in the sample.
Here's an analysis of the provided 510(k) summary, focusing on acceptance criteria and the supporting study:
The document describes a Special 510(k) submission for a modified Creatinine assay for urine application. The acceptance criteria for the modified assay are implicitly based on demonstrating substantial equivalence to a predicate device (Roche Creatinine assay urine application on the Hitachi 917 Analyzer) and a previously cleared version of the Creatinine assay (K061193) on the Abbott AEROSET® System and ARCHITECT® cSystems.
The primary study conducted is a comparative performance study.
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria Category | Specific Metric (Implicit) | Predicate/Reference Performance (Roche Creatinine assay on Hitachi 917 Analyzer) | Modified Device Performance (AEROSET System creatinine assay) | Modified Device Performance (ARCHITECT c8000 System creatinine assay) | Meets Criteria? |
|---|---|---|---|---|---|
| Method Comparison | Correlation Coefficient (R) vs. Roche Creatinine assay on Hitachi 917 Analyzer | - (Reference) | 0.9992 | 0.9990 | Yes |
| Method Comparison | Slope vs. Roche Creatinine assay on Hitachi 917 Analyzer | - (Reference) | 1.01 | 0.97 | Yes |
| Method Comparison | Y-intercept (mg/dL) vs. Roche Creatinine assay on Hitachi 917 Analyzer | - (Reference) | -0.43 | 0.36 | Yes |
| Method Comparison | Correlation Coefficient (R) vs. AEROSET System Creatinine assay (for ARCHITECT c8000 comparison) | 0.9992 (AEROSET) | N/A | 0.9992 | Yes |
| Method Comparison | Slope vs. AEROSET System Creatinine assay (for ARCHITECT c8000 comparison) | 1.01 (AEROSET) | N/A | 0.96 | Yes |
| Method Comparison | Y-intercept (mg/dL) vs. AEROSET System Creatinine assay (for ARCHITECT c8000 comparison) | -0.43 (AEROSET) | N/A | 1.23 | Yes |
| Linearity | Range | 5.00 to 740.00 mg/dL (Implied predicate range is similar or within this) | 5.00 to 740.00 mg/dL | 5.00 to 740.00 mg/dL | Yes |
| Limit of Quantitation (Sensitivity) | Value (for urine application) | 5.00 mg/dL (Implied predicate value is similar) | 5.00 mg/dL | 5.00 mg/dL | Yes |
| Precision | Total %CV for Level 1 (urine application on ARCHITECT c8000 System) | (Implied acceptable range) | N/A | 1.34% | Yes |
| Precision | Total %CV for Level 2 (urine application on ARCHITECT c8000 System) | (Implied acceptable range) | N/A | 1.27% | Yes |
Note: The document states "acceptable correlation" and "similar Performance Characteristics," implying the reported values met predetermined acceptance criteria for substantial equivalence to the predicate and the previously cleared device. Specific quantitative acceptance thresholds for correlation coefficients, slopes, intercepts, or %CV are not explicitly listed, but the reported values are presented as meeting these criteria.
2. Sample Size Used for the Test Set and the Data Provenance
- Sample Size: The document does not explicitly state the sample size (number of urine samples) used for the comparative performance studies. It mentions "Comparative performance studies were conducted" but does not quantify the number of samples.
- Data Provenance: Not specified. The document does not mention the country of origin of the data or whether the study was retrospective or prospective. It only indicates that "Comparative performance studies were conducted."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and the Qualifications of Those Experts
This type of diagnostic device (Creatinine assay) does not rely on human experts to establish "ground truth" for individual test results in the way image analysis or clinical diagnosis devices do. The "ground truth" for the test set is established by the performance of the predicate device (Roche Creatinine assay urine application on the Hitachi 917 Analyzer) and the previously cleared device (Creatinine assay on the Abbott AEROSET® System). The performance metrics of the modified device are compared against the measurements obtained from these established methods.
4. Adjudication Method for the Test Set
Not applicable. As this is a quantitative chemical assay, "adjudication" in the sense of multiple human readers resolving discrepancies is not relevant. The comparison is made directly between numerical measurements from different instruments/assays.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
- No, an MRMC comparative effectiveness study was not done. This type of study is relevant for devices that involve human interpretation (e.g., radiologists reading images) where the AI assists the human. This 510(k) is for an in vitro diagnostic assay, which provides a direct quantitative measurement, not an interpretation aid.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
- Yes, in essence, standalone performance was assessed. The Creatinine assay itself is a standalone algorithm/method that directly measures creatinine levels. Its performance is evaluated by comparing its quantitative results against those of predicate methods. There is no "human-in-the-loop" once the sample is loaded and the assay begins to run.
7. The Type of Ground Truth Used
The ground truth for evaluating the modified Creatinine assay is the measurements obtained from the legally marketed predicate device (Roche Creatinine assay urine application on the Hitachi 917 Analyzer) and the previously cleared version of the same Creatinine assay (on the Abbott AEROSET® System). This is a form of comparative measurement ground truth, where the reference standard is another recognized and validated method.
8. The Sample Size for the Training Set
The document does not explicitly mention a "training set" in the context of an algorithm that learns from data. This submission is for an assay, not a machine learning algorithm that requires a separate training phase. The "modifications" were to calibration and assay parameters, implying adjustments based on known chemical principles and potentially internal studies, rather than a data-driven machine learning training set.
9. How the Ground Truth for the Training Set Was Established
Not applicable. As noted above, this is an in vitro diagnostic assay based on chemical reactions, not a machine learning algorithm with a training set. The "ground truth" for the calibration and assay parameters would be based on the principles of the Jaffe reaction, and reference standards like NIST SRM 914 and NIST SRM 967, which are IDMS traceable.
§ 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.