(171 days)
The S-Test Creatinine Reagent is intended for the quantitative determination of Creatinine concentration in serum or heparin plasma using the S40 Clinical Analyzer. 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. This test is intended for use in clinical laboratories or physician office laboratories. For in vitro diagnostic use only.
The S-Test Creatinine (CRE) reagent cartridge, used with the S40 Clinical Analyzer, is intended for quantitative in vitro diagnostic determination of CRE in serum or heparin plasma based on a photometric test measuring the formation of a reddish-purple pigment in a coupled enzymatic reaction.
The provided document describes the performance data for the S-Test CRE Reagent, a device for quantitative in vitro diagnostic determination of Creatinine in serum or heparin plasma.
Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't explicitly state "acceptance criteria" as a separate section with numerical targets. Instead, it presents performance data for precision, accuracy, and sensitivity, implying these are the metrics against which the device's performance is judged for substantial equivalence to a predicate device.
| Performance Metric | Acceptance Criteria (Implied) | Reported Device Performance |
|---|---|---|
| Precision | Within-run CV: Low | - In-house: 1.3 to 9.6% at three CRE levels over 22 days |
| - POL sites (3): 1.0 to 10.1% over five days | ||
| Total CV: Low | - In-house: 4.3 to 17.2% | |
| - POL sites (3): 1.3 to 10.8% | ||
| Accuracy (Correlation to Comparative Method) | Correlation Coefficient (r): High (close to 1) | - In-house: 0.998 for 65 samples (0.6 to 14.6 mg/dL) |
| - POL sites (4): 0.997 to 0.999 | ||
| Standard Error Estimate: Low | - In-house: 0.16 | |
| - POL sites (4): 0.25 to 0.34 | ||
| Confidence Interval Slope: Close to 1 (indicating proportional agreement) | - In-house: 1.002 to 1.031 | |
| - POL sites (4): 1.003 to 1.060 | ||
| Confidence Interval Intercept: Close to 0 (indicating no constant bias) | - In-house: -0.20 to -0.10 | |
| - POL sites (4): -0.38 to 0.10 | ||
| Sensitivity (Detection Limit) | Low (able to detect small amounts) | 0.3 mg/dL |
2. Sample Size Used for the Test Set and Data Provenance:
- Test Set Sample Size:
- Precision (in-house): Not explicitly stated as a number of samples, but "three CRE levels for 22 days" implies multiple measurements at each level.
- Precision (POL): Not explicitly stated as a number of samples, but "three separate Physician Office Laboratory (POL) sites and in-house over five days" implies multiple measurements at each site.
- Accuracy (in-house correlation): 65 samples.
- Accuracy (POL correlation): Not explicitly stated as the number of samples per site, but implies multiple samples were tested at "four separate POL sites."
- Data Provenance:
- The studies were conducted in-house by Alfa Wassermann Diagnostic Technology, LLC, and at Physician Office Laboratory (POL) sites.
- The data appears to be prospective, as it describes the conduct of new studies for the purpose of demonstrating the device's performance. The nature of the "comparative method" used for accuracy also suggests a controlled test.
- The country of origin is implicitly the United States, given the submission to the FDA.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts:
This information is not provided in the document. For an in vitro diagnostic device like Creatinine, the "ground truth" for accuracy studies is typically established by a recognized reference method or a well-established comparative method, not by individual experts or their consensus. The document explicitly states "a comparative method (x)" was used. The qualifications of the personnel operating this comparative method are not detailed.
4. Adjudication Method for the Test Set:
This information is not applicable to this type of device and study. Adjudication methods (like 2+1 or 3+1) are typically used for qualitative or subjective assessments (e.g., image interpretation) where there might be disagreement among reviewers, requiring a process to establish a consensus ground truth. For quantitative assays like Creatinine, the "truth" is derived from a measurement device (the comparative method) rather than expert opinion requiring adjudication.
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 information is not applicable. An MRMC study is relevant for devices involving human interpretation (e.g., radiologists reading medical images). The S-Test CRE Reagent is an automated in vitro diagnostic assay for chemical analysis; it does not involve human "readers" in the context of interpretation that would be augmented by AI.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
Yes, a standalone performance study was done. The entire performance data section describes the analytical performance of the S-Test CRE Reagent and S40 Clinical Analyzer system operating independently, determining Creatinine levels. There's no mention of a human "in-the-loop" influencing the results of the assay itself. The results reported (precision, accuracy, sensitivity) are inherent to the device's analytical function.
7. The Type of Ground Truth Used:
The ground truth for the accuracy studies (correlation) was established by a comparative method. The document refers to "a comparative method (x)" against which the S-Test CRE (y) was evaluated. This implies an independent, generally accepted analytical method for Creatinine measurement was used as the reference standard. It is not expert consensus, pathology, or outcomes data.
8. The Sample Size for the Training Set:
This information is not provided or applicable in the context described. The S-Test CRE Reagent is a chemical assay, not an AI/ML-based algorithm that would typically require a distinct "training set" to develop. The performance studies described are for validation/testing of the established reagent formulation and analytical method.
9. How the Ground Truth for the Training Set Was Established:
This information is not applicable as there is no mention or indication of a training set as understood in the context of AI/ML or complex analytical model development. The development of a chemical reagent involves formulation and optimization, followed by validation studies against established methods to demonstrate performance. The "ground truth" for developing such a reagent would be derived from the fundamental chemical principles and established analytical standards for Creatinine measurement, not from a distinct "training set" with established ground truth labels.
§ 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.