(25 days)
Abbott AxSYM® Troponin-I is a Microparticle Enzyme Immunoassay (MEIA) for the quantitative determination of cardiac troponin-I in human serum or plasma on the Abbott AxSYM System. Measurements obtained by this device are used to assist in the diagnosis of acute myocardial infarction (AMI).
AxSYM Troponin-I is a Microparticle Enzyme Immunoassay (MEIA) for the quantitative determination of cardiac troponin-I in human serum or plasma. AxSYM Troponin-I is calibrated with Abbott Troponin-I Calibrators. Abbott Troponin-I Controls are assayed for the verification of the accuracy and precision of the AxSYM System. Both assays are automated, in vitro immunoassays that use antibodies specific for the cardiac isotype of troponin-I. The fluorescent signal measured by both assays is directly proportional to the concentration of cardiac troponin-I in the sample.
Acceptance Criteria and Study for Abbott AxSYM® Troponin-I
This document describes the acceptance criteria and the study conducted to demonstrate the substantial equivalence of the Abbott AxSYM® Troponin-I assay.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for the AxSYM Troponin-I assay were implicitly defined by demonstrating substantial equivalence to a predicate device and achieving clinically acceptable sensitivity and specificity for the diagnosis of Acute Myocardial Infarction (AMI). While specific quantitative acceptance criteria for sensitivity and specificity were not explicitly stated as "acceptance criteria" in the provided text, the reported performance was considered sufficient for regulatory approval.
| Metric | Acceptance Criteria (Implicit) | Reported Device Performance (AxSYM Troponin-I) |
|---|---|---|
| Correlation with Predicate | Strong correlation (e.g., Spearman coefficient > 0.8) | Spearman correlation coefficient: 0.851 |
| Clinical Sensitivity | High sensitivity using WHO criteria for AMI | 93.9% |
| Clinical Specificity | High specificity using WHO criteria for AMI | 93.4% |
2. Sample Size Used for the Test Set and Data Provenance
- Test Set Sample Size:
- Clinical Study: 246 patients, representing 689 observations (serial samples).
- Method Comparison: 158 specimens for the Passing-Bablok linear regression analysis.
- Data Provenance: The document does not explicitly state the country of origin. The study was described as a "multi-center clinical study," which generally implies prospective data collection, especially given the serial sampling to rule in/rule out AMI. The method comparison data would also be considered prospective.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications
- The ground truth for AMI diagnosis in the clinical study was based on the World Health Organization (WHO) criteria for AMI. The document does not specify the number or qualifications of individual experts who applied these criteria to establish the ground truth for each patient. This suggests that the ground truth was established by clinical teams at the participating centers following established medical guidelines, rather than by a panel of independent, reviewing experts for the purpose of the study.
4. Adjudication Method for the Test Set
- The document does not describe a specific adjudication method (e.g., 2+1, 3+1) for establishing the ground truth regarding AMI diagnosis. As mentioned above, the diagnosis was based on WHO criteria, implying a standard clinical diagnostic process.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No, a multi-reader multi-case (MRMC) comparative effectiveness study was not performed. This device is an in vitro diagnostic (IVD) assay (a laboratory test) that provides a quantitative result. Its effectiveness is assessed by its analytical performance and clinical accuracy in diagnosing a condition, not by human reader interpretation or improved human reader performance with AI assistance.
6. Standalone Performance Study
- Yes, a standalone performance study was done. The clinical sensitivity (93.9%) and specificity (93.4%) were determined for the AxSYM Troponin-I assay alone, using a diagnostic cutoff of 2.0 ng/mL, against the clinical diagnosis of AMI based on WHO criteria. This represents the algorithm's (assay's) performance without human interpretation or intervention in the diagnostic output.
7. Type of Ground Truth Used
- Clinical Diagnosis / Outcomes Data (for sensitivity/specificity): The primary ground truth for the clinical study was the World Health Organization (WHO) criteria for AMI. This is a well-established clinical definition for myocardial infarction.
- Predicate Device Measurement (for correlation): For the method comparison, the Dade® Stratus® Cardiac Troponin-I Fluorometric Enzyme Immunoassay served as the reference for comparison, indicating that its measurements were considered the "ground truth" for evaluating analytical agreement.
8. Sample Size for the Training Set
- The document does not explicitly mention a "training set" in the context of machine learning or AI models. The AxSYM Troponin-I is an immunoassay, which does not typically involve traditional machine learning training sets in the same way an AI algorithm for image analysis would. Development and calibration would involve various internal validation samples, but these are not usually referred to as a "training set" in this context.
9. How the Ground Truth for the Training Set Was Established
- As noted above, the concept of a training set with established ground truth in the AI/ML sense does not directly apply here. For standard immunoassay development, the "ground truth" for calibrator and control materials is established through rigorous analytical methods, often involving reference methods or gravimetric preparation of known analyte concentrations. The accuracy and precision of these materials are critical for the assay's performance.
§ 862.1215 Creatine phosphokinase/creatine kinase or isoenzymes test system.
(a)
Identification. A creatine phosphokinase/creatine kinase or isoenzymes test system is a device intended to measure the activity of the enzyme creatine phosphokinase or its isoenzymes (a group of enzymes with similar biological activity) in plasma and serum. Measurements of creatine phosphokinase and its isoenzymes are used in the diagnosis and treatment of myocardial infarction and muscle diseases such as progressive, Duchenne-type muscular dystrophy.(b)
Classification. Class II.