Search Results
Found 1 results
510(k) Data Aggregation
(126 days)
The Elecsys FT3 is an in vitro quantitative determination of free triiodothyronine (FT3) in human serum and plasma. Triiodothyronine is one of the thyroid hormones present in serum which regulate metabolism.
The Elecsys FT3 employs a competitive test principle with polyclonal antibodies directed against T3 and with streptavidin microparticles and electrochemiluminescence detection.
1st Incubation: Sample (30 µl) and a specific anti-T3 antibody labeled with a ruthenium complex.
2nd Incubation: After addition of biotinylated T3 and streptavidin-coated microparticles, the still-free binding sites of the labeled antibody become occupied, with formation of an antibody-hapten complex. The entire complex is bound to the solid phase via interaction of biotin and streptavidin.
The reaction mixture is aspirated into the measuring cell where the microparticles are magnetically captured onto the surface of the electrode.
The medical device in question is the Elecsys® FT3, an in vitro quantitative determination of free triiodothyronine (FT3) in human serum and plasma.
1. Acceptance Criteria and Reported Device Performance
The acceptance criteria for the Elecsys FT3 device are not explicitly stated as distinct pass/fail thresholds in the provided document. Instead, the performance characteristics are presented in comparison to a predicate device (Enzymun-Test® FT3) and, for method comparison, to a reference method (Elkins Equilibrium Dialysis). The substantial equivalence is based on demonstrating comparable performance.
Here's a table summarizing the reported device performance, with implicit acceptance being comparable to the predicate or demonstrating robust performance metrics:
| Feature | Acceptance Criteria (Implicit from Predicate/Reference) | Elecsys FT3 Performance |
|---|---|---|
| Precision (Within-run %CV) | Comparable to Enzymun-Test FT3 (3.8 - 2.3%) | PreciControl Universal 1: 2.0% |
| PreciControl Universal 2: 2.5% | ||
| HS1: 2.3% | ||
| HS2: 2.1% | ||
| HS3: 2.3% | ||
| (Generally better or comparable to predicate) | ||
| Precision (Total run %CV) | Comparable to Enzymun-Test FT3 (4.5 - 2.4%) | PreciControl Universal 1: 3.6% |
| PreciControl Universal 2: 3.3% | ||
| HS1: 4.7% | ||
| HS2: 3.1% | ||
| HS3: 2.7% | ||
| (Generally comparable to or better than predicate) | ||
| Lower Detection Limit (LDL) | Comparable to Enzymun-Test FT3 (0.47 pmol/l, 0.5 pg/ml) | 0.40 pmol/l (0.26 pg/ml) |
| (Lower, indicating better sensitivity) | ||
| Assay Range | Comparable to Enzymun-Test FT3 (0.47-46 pmol/l) | 0.40 - 50 pmol/l (0.26 - 32 pg/ml) |
| (Slightly wider upper range and lower LDL) | ||
| Method Comparison (vs. Enzymun-Test FT3) | Strong correlation (e.g., r > 0.90) | Least Squares: y = -0.22 + 0.90x, r = 0.94 |
| Passing/Bablok: y = -1.45 + 1.06x, r = 0.94 | ||
| (Strong correlation, close to ideal y=x line) | ||
| Method Comparison (vs. Elkins Equilibrium Dialysis) | Strong correlation (e.g., r > 0.95, given it's a reference method) | Least Squares: y = 0.99x + 0.203, r = 0.998 |
| (Excellent correlation with the reference method) | ||
| Interfering Substances | No significant interference at specified concentrations | Hemoglobin: No interference up to 1 g/dl |
| Lipemia: No interference up to 1500 mg/dl | ||
| Bilirubin: No interference up to 25 mg/dl | ||
| Biotin: No interference up to 30 ng/ml | ||
| Specificity (% cross-reaction) | Low cross-reactivity for related substances | D-T3: 98.86% (high, as expected due to similarity to L-T3) |
| L-T4: 0.115% | ||
| D-T4: 0.115% | ||
| L-rT3: 0.007% | ||
| 3,3',5-tri-iodothyroacetic acid: 106.4% | ||
| 3,3',5,5'-tetra-iodothyroacetic acid: 0.007% | ||
| (Generally low for non-T3 thyroid hormones, with expected high for similar compounds) |
2. Sample Sizes and Data Provenance for Test Set
- Precision Study (Elecsys FT3):
- Sample Size (N): 60 for each of 5 different samples (PreciControl Universal 1, PreciControl Universal 2, HS1, HS2, HS3).
- Data Provenance: Not explicitly stated, but the methodology refers to NCCLS (Modified) (EP5-T2), which are standard clinical laboratory guidelines. Implies clinical laboratory samples. Retrospective or prospective is not specified.
- Precision Study (Enzymun-Test FT3, Predicate):
- Sample Size (N): 120 for each of 3 different samples (1, 2, 3).
- Data Provenance: Not explicitly stated. Methodology refers to NCCLS "Midi" (EP5-T).
- Method Comparison vs. Enzymun-Test FT3:
- Sample Size (N): 298.
- Data Provenance: Not explicitly stated. Assumed to be human serum/plasma samples. Retrospective or prospective is not specified.
- Method Comparison vs. Elkins Equilibrium Dialysis:
- Sample Size (N): 22.
- Data Provenance: Not explicitly stated. Assumed to be human serum/plasma samples. Retrospective or prospective is not specified. Given the small number, it might be a specific set of clinical samples where equilibrium dialysis was performed.
3. Number of Experts and Qualifications for Ground Truth (Test Set)
This device is an in vitro diagnostic (IVD) assay for measuring a specific analyte (FT3). The "ground truth" for such devices is typically established through analytical methods and comparison to established reference methods, not by human expert opinion like in imaging studies.
- Elkins Equilibrium Dialysis is referred to as a "reference method" for direct measurement of fT4 and fT3. This method itself serves as a highly accurate "ground truth" and does not involve human expert consensus or adjudication in interpreting the result. It's a laboratory gold standard for free thyroid hormone measurement.
Therefore, the concept of "number of experts" and their "qualifications" for establishing ground truth in the context of an IVD assay's performance evaluation (like for diagnostic accuracy in an imaging test) is not directly applicable here.
4. Adjudication Method for the Test Set
Not applicable. For an IVD device measuring an analyte, the "ground truth" is determined by the result of the reference method (e.g., Elkins Equilibrium Dialysis) or the predicate device, not by adjudication of human expert interpretations.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No. This is an in vitro diagnostic (IVD) assay, not an imaging or interpretation-based diagnostic device. MRMC studies are not relevant for evaluating the performance of an analytical assay.
6. Standalone (Algorithm Only) Performance Study
Yes, the studies presented are all standalone performance evaluations of the Elecsys FT3 device (the "algorithm" in this context refers to the assay's chemical and detection methodology). The precision, sensitivity, assay range, method comparisons, and interference studies directly assess the device's inherent analytical performance without human intervention in the result determination process once the sample is loaded.
7. Type of Ground Truth Used
- Reference Method: For the method comparison study, Elkins Equilibrium Dialysis served as a robust reference method for determining "true" FT3 concentrations.
- Predicate Device: The Enzymun-Test® FT3 served as a comparator for demonstrating substantial equivalence. The results from the predicate were effectively a "ground truth" for comparison purposes in this context.
- Known Concentrations: For precision and sensitivity studies, quality control materials (e.g., PreciControl Universal) with known or targeted concentrations and human serum samples (HS1, HS2, HS3) were used, providing a basis for evaluating repeatability and reproducibility.
8. Sample Size for the Training Set
The document describes performance characteristics, not the development of a machine learning algorithm that requires a "training set." This device is a biochemical assay. Therefore, the concept of a "training set" in the context of machine learning is not applicable. The development and optimization of the assay would involve various experiments and technical iterations to establish reagents, protocols, and instrument parameters, but this is distinct from "training data" for an AI model.
9. How Ground Truth for the Training Set Was Established
Not applicable, as there is no "training set" in the machine learning sense for this device. The biochemical principles and laboratory testing methods inherently define the assay's "truth."
Ask a specific question about this device
Page 1 of 1