(84 days)
This Enzyme immunoassay is used for the quantitative estimation of non-protein bound thyroxine(Free T4) in human serum. This is an in vitro diagnostic device used to assist in the assessment of thyroid function.
The Biostride Free T4 EIA Test Kit is an in vitro enzyme immunoassay for the quantitative estimation of freeT4, thyroxine, in human serum. This Free T4 test is a colorimetric microtiter plate enzyme immunoassay (EIA).
Acceptance Criteria and Device Performance Study for Biostride Free T4 EIA Test Kit
1. Acceptance Criteria and Reported Device Performance
The Biostride Free T4 EIA Test Kit was evaluated against the Abbott AxSYM, a legally marketed predicate device. The primary acceptance criteria were demonstrating similar performance characteristics and excellent correlation of results.
| Metric | Acceptance Criteria (based on predicate device) | Reported Device Performance (Biostride Free T4 EIA Test Kit) |
|---|---|---|
| Correlation Coefficient (r) | Excellent correlation with predicate (Abbott AxSYM) | 0.96 |
| Intercept | Similar to predicate | 0.13 ng/dL |
| Slope | Similar to predicate | 0.91 |
| Precision (CVs) | Similar to predicate (Abbott system reported CVs between 2.10-9.9%) | 6%, 3% |
| Reproducibility (CVs) | Similar to predicate | 19%, 5%, 4% |
| Sensitivity | Similar to predicate (Abbott AxSYM: 0.04 ng/dL) | 0.08 ng/dL (defined as 2 SD from 0.0 g/dL calibrator) |
| Specificity to D-T4 | Similar to predicate (Abbott system: approximately 100%) | Approximately 100% |
Conclusion: The study demonstrated that the Biostride Free T4 EIA Test Kit met the acceptance criteria by showing similar performance characteristics and excellent correlation of results when compared to the Abbott AxSYM.
2. Sample Size and Data Provenance
- Sample Size for Test Set: 171 patient samples
- Data Provenance: Not explicitly stated, however, the context of clinical testing typically implies the samples were collected from a relevant patient population. (Prospective/Retrospective not specified)
3. Number of Experts and Qualifications for Ground Truth
Not applicable. This was a comparative study against a predicate device, not a study requiring expert interpretation for ground truth establishment. The ground truth was effectively the results obtained from the predicate device, which is an established clinical assay.
4. Adjudication Method for Test Set
Not applicable. The study involved direct comparison of quantitative results between two assays, not interpretation by multiple human readers requiring adjudication.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This study is for an in-vitro diagnostic device (EIA test kit), which generates quantitative results and does not involve human readers interpreting images or data in the same way an MRMC study would.
6. Standalone Performance Study
Yes, a standalone performance was done for the Biostride Free T4 EIA Test Kit by evaluating its precision, reproducibility, sensitivity, and specificity. However, these were then presented in comparison to the predicate device to establish substantial equivalence.
7. Type of Ground Truth Used
The "ground truth" for this study was essentially the quantitative Free T4 values obtained from the Abbott AxSYM, which is a widely accepted and legally marketed predicate device for Free T4 estimation. This can be considered a form of reference standard comparison.
8. Sample Size for Training Set
The document does not explicitly mention a separate "training set" or its size. In a device like an EIA test kit, the development and optimization (which might be analogous to "training") typically involve internal validation studies to establish the assay's performance characteristics, rather than a distinct "training set" of patient data in the machine learning sense. The described study focuses on validation against a predicate device.
9. How Ground Truth for Training Set was Established
As no explicit training set is mentioned in the provided text, the method for establishing its ground truth is also not detailed. Device development often relies on a combination of analytical validation, using prepared samples with known concentrations, and internal clinical samples.
§ 862.1695 Free thyroxine test system.
(a)
Identification. A free thyroxine test system is a device intended to measure free (not protein bound) thyroxine (thyroid hormone) in serum or plasma. Levels of free thyroxine in plasma are thought to reflect the amount of thyroxine hormone available to the cells and may therefore determine the clinical metabolic status of thyroxine. Measurements obtained by this device are used in the diagnosis and treatment of thyroid diseases.(b)
Classification. Class II.