(114 days)
Sigma Diagnostics ACCUCLOT™ Thrombin Time Reagent (A8713/A4589) is a device intended to measure fibrinogen concentration and to detect fibrin or fibrinogen split products for the evaluation of bleeding disorders.
Sigma Diagnostics' ACCUCLOT™ Thrombin Time Reagent is intended for use as a screening procedure to detect functional fibrinogen and thrombin inhibitors such as heparin, in citrated plasma. The ACCUCLOT™ Thrombin Time Reagent provides thrombin for fibrinogen hydrolysis and is able to detect normal fibrinogen function even in the presence of severe coagulation abnormalities such as hemophilia (Factor VIII or Factor IX deficiency) or a decrease in factor levels associated with vitamin K deficiency.
The provided text describes the safety and effectiveness of the Sigma Diagnostics' ACCUCLOT™ Thrombin Time Reagent, primarily by demonstrating its substantial equivalence to a legally marketed predicate device, Organon's Thromboquik™ Thrombin Time Reagent.
1. Table of Acceptance Criteria and Reported Device Performance:
| Acceptance Criteria Category | Acceptance Criteria (Predicate Equivalent) | Reported Device Performance (ACCUCLOT™ Thrombin Time Reagent) |
|---|---|---|
| Correlation with Predicate Device (Organon Thromboquik™) on Different Instruments | High correlation (r² close to 1) with the predicate device across various coagulation analyzers. No specific numerical threshold for r² is given as an acceptance criterion, but the provided r² values indicate strong correlation. | AMAX Optical: Y = 2.11x - 13.33, r² = 0.978 (N=101) |
| AMAX Mechanical: Y = 2.87x - 18.10, r² = 0.972 (N=101) | ||
| KC4a: Y = 1.95x - 7.26, r² = 0.959 (N=49) | ||
| Precision (Within-run CV) | Less than 7% | Less than 7% |
| Precision (Total Precision) | Less than 6% | Less than 6% |
| Heparin Sensitivity | Detect heparin levels corresponding to 0.2 U/mL and up to at least 0.8 U/mL (implied equivalence to predicate's performance in detecting these levels) | Sensitive to heparin levels corresponding to 0.2 heparin U/mL and up to at least 0.8 heparin U/mL. |
| Fibrinogen Sensitivity | Detect abnormal low fibrinogen levels (implied for equivalence). No specific numerical threshold is given for the predicate, but ACCUCLOT™ shows sensitivity starting at 98 mg/dL. | Demonstrated sensitivity for abnormal low fibrinogen levels starting at 98 mg/dL fibrinogen. |
Study Proving Acceptance Criteria:
The study proving the device meets the acceptance criteria is a substantial equivalence study comparing the Sigma Diagnostics' ACCUCLOT™ Thrombin Time Reagent to Organon's Thromboquik™ Thrombin Time Reagent (the predicate device).
2. Sample Sizes Used for the Test Set and Data Provenance:
- Correlation Study:
- AMAX Optical & AMAX Mechanical: N = 101 plasma samples (normal and abnormal)
- KC4a: N = 49 plasma samples (normal and abnormal)
- Precision Study: Normal and abnormal control plasmas were used, but the specific number of samples or replicates is not explicitly stated, only that the "within run CV" and "total precision" were measured.
- Heparin/Fibrinogen Sensitivity: The text states the reagent's sensitivity but does not provide specific sample sizes for these evaluations.
- Data Provenance: The document does not specify the country of origin of the data. The study appears to be retrospective in the sense that existing plasma samples (normal and abnormal) were used to compare the new device against the predicate.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Qualifications:
Not applicable. This study does not involve expert interpretation of results to establish ground truth in the way medical imaging or clinical diagnostics typically would. The "ground truth" for the correlation study is the result obtained from the legally marketed predicate device (Organon's Thromboquik™). For precision, it's the expected value of the control plasmas.
4. Adjudication Method for the Test Set:
Not applicable. This is a quantitative comparison against a predicate device, not an interpretation task requiring adjudication.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done:
No, an MRMC comparative effectiveness study was not done. This study focuses on the analytical performance of the new reagent compared to a predicate, not on human reader performance with or without AI assistance.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done:
Yes, the studies described are essentially "standalone" in nature, comparing the performance of the ACCUCLOT™ reagent (the "algorithm" or test method) directly against the predicate Thromboquik™ reagent. There is no human-in-the-loop component described for interpreting the results beyond standard laboratory technician procedures.
7. The Type of Ground Truth Used:
The primary "ground truth" used for substantial equivalence is the results obtained from the legally marketed predicate device (Organon's Thromboquik™ Thrombin Time Reagent). For the precision studies, the ground truth would be the known values of the normal and abnormal control plasmas.
8. The Sample Size for the Training Set:
Not applicable. This study does not describe a machine learning model with a separate training set. The "training" in this context refers to the development and optimization of the reagent itself, not an algorithm.
9. How the Ground Truth for the Training Set Was Established:
Not applicable, as there's no machine learning training set described. The "ground truth" for the development of the reagent would stem from established scientific principles of coagulation testing and chemical reactions.
§ 864.7875 Thrombin time test.
(a)
Identification. A thrombin time test is a device used to measure fibrinogen concentration and detect fibrin or fibrinogen split products for the evaluation of bleeding disorders.(b)
Classification. Class II (performance standards).