(61 days)
Sigma Diagnostics Creatinine Reagent is intended to measure creatinine levels in serum, plasma, Sigma Diagos monitoring renal dialysis, and as a calculation basis for measuring other urine analytes.
The Sigma Diagnostics procedure is a modification of the Jaffe reaction and is highly adaptable to automation. The rate of color change following the addition of a serum, plasma or urine sample to an alkaline picrate solution is measured between 480 and 520 nm and is proportional to the creatinine concentration in the test specimen.
Here's a breakdown of the acceptance criteria and study information for the Sigma Diagnostics Creatinine Reagent, based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria Category | Specific Criteria/Metric | Reported Device Performance | Comments |
|---|---|---|---|
| Method Comparison | Correlation Coefficient (Serum) | 0.999 | Against Boehringer Mannheim Diagnostics (BMD) using manual procedure. |
| Regression Equation (Serum) | y = 1.11x + 0.05 | Against BMD using manual procedure. | |
| Correlation Coefficient (Urine) | 0.998 | Against BMD using manual procedure. | |
| Regression Equation (Urine) | y = 1.13x - 0.17 | Against BMD using manual procedure. | |
| Precision | Within-run precision (Serum) | Acceptable values can be replicated | Details on specific CV% or standard deviation not provided, but stated as acceptable. |
| Total precision (Serum) | Acceptable values can be replicated | Details on specific CV% or standard deviation not provided, but stated as acceptable. | |
| Linearity | Linear Range | Up to 25 mg/dL | Confirmed as linear. |
Study Information
2. Sample sizes used for the test set and the data provenance:
- Test Set Sample Size:
- Serum samples: 128
- Urine samples: The exact number is not explicitly stated, but derived from "comparison studies against BMD using the manual procedure a correlation coefficient of 0.998 and a regression equation y = 1.13x -0.17 was obtained with urine samples." It implies a similar comparative study was performed.
- Data Provenance: Not explicitly stated (e.g., country of origin). The studies appear to be retrospective method comparison studies, using existing samples to compare the Sigma Diagnostics Creatinine Reagent against a predicate device.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable (N/A): This study is a method comparison for an in vitro diagnostic (IVD) device measuring a biochemical analyte (creatinine). The "ground truth" for method comparison studies like this is typically the result obtained from the predicate device (Boehringer Mannheim Diagnostics Creatinine Reagent), not expert consensus. Therefore, expert involvement in establishing ground truth for the test set measurements is not relevant in the way it would be for image-based diagnostics.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- None: Adjudication methods are typically used in studies involving human interpretation or subjective assessment. For analytical performance studies of IVD devices comparing quantitative measurements, adjudication is not a standard practice. The "ground truth" is established by the reference method (predicate device measurements).
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:
- N/A: This is an in vitro diagnostic device for measuring creatinine. MRMC studies and "human readers improve with AI" are concepts specific to AI-powered diagnostics that analyze images or complex data requiring human interpretation. This device performs a biochemical measurement.
6. If a standalone (i.e. algorithm only without human-in-the loop performance) was done:
- Standalone (algorithm/reagent only) performance was done: The study focuses solely on the analytical performance of the Sigma Diagnostics Creatinine Reagent in measuring creatinine concentrations, comparing its results directly to those of the predicate device (Boehringer Mannheim Diagnostics Creatinine Reagent). There is no "human-in-the-loop" component in the described performance evaluation.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" or reference standard for this study was the results obtained from the legally marketed predicate device, Boehringer Mannheim Diagnostics Creatinine Reagent (No. 1050702). This is a common form of ground truth for demonstrating substantial equivalence of a new IVD device to an existing one.
8. The sample size for the training set:
- N/A: This document describes analytical performance testing for a chemical reagent, not a machine learning model. Therefore, there is no "training set" in the context of AI/ML.
9. How the ground truth for the training set was established:
- N/A: As there is no training set for an AI/ML model, the concept of establishing ground truth for a training set is not applicable here.
§ 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.