(181 days)
The STA® - Cephascreen® kits provide reagents for the determination of the activated partial thromboplastin time (APTT) in citrated plasma on the STA® line of analyzers suitable to these reagents.
The STA®-Cephascreen kits provide reagents for the determination of the activated partial thromboplastin time (APTT) according to Langdell R.D. et al. (1) and Larrieu M. J., Weilland C. (2) by analyzers of the STA® line suitable to these reagents.
STA®-Cephascreen ®: reagent containing cephalin (platelet substitute), prepared from rabbit cerebral tissues (2) and a polyphenolic activator (patent pending) in a buffered medium.
The STA®-Cephascreen ® is available in two different kit sizes:
- STA®-Cephascreen®©(REF00308) containing 12x4 mL vials ready for . use reagent
- STA®-Cephascreen®쓰(REF 00310) containing 12x10 mL vials of ready . for use reagent
The STA®-Cephascreen® reagents are provided in liquid form, ready for use after stabilization and mixing when a vial is opened.
Here's an analysis of the provided text regarding the STA®-Cephascreen Kit, focusing on acceptance criteria and the supporting study:
The document describes a 510(k) summary for the STA®-Cephascreen Kit, which is a reagent for determining activated partial thromboplastin time (APTT). The primary purpose of this submission is to demonstrate substantial equivalence to a predicate device, the STA®-C.K.Prest® kit.
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't explicitly state "acceptance criteria" for the STA®-Cephascreen Kit in the traditional sense of numerical thresholds for sensitivity, specificity, or accuracy compared to a gold standard. Instead, the study aimed to demonstrate substantial equivalence to the predicate device.
The reported performance is based on the correlation between the new device and the predicate device.
| Metric (Acceptance Criteria - implied by the comparative study) | Reported Device Performance (STA®-Cephascreen Kit vs. STA®-C.K.Prest® Kit) |
|---|---|
| Correlation Coefficient (r) | r = 0.943 |
| Slope (a) of the regression line | a = 0.78 |
| Y-intercept (b) of the regression line | b = 8.2 |
| Interpretation: Substantial Equivalence | Based on the range of correlating data, STA®-Cephascreen® is substantially equivalent to the predicate device. This is the ultimate "acceptance" for a 510(k) submission. |
2. Sample Size Used for the Test Set and Data Provenance:
- Sample Size: 125 plasma samples.
- 40 plasmas from presumed normal individuals
- 20 plasmas from patients receiving unfractionated heparin (UFH) therapy
- 20 plasmas from patients receiving low molecular weight heparin (LMWH) therapy
- 15 plasmas from patients receiving oral anticoagulant (AVK) therapy
- 10 LA positive plasma samples
- 10 plasmas from patients with factor VIII deficiency (F. VIII Def.)
- 10 plasmas from patients with factor IX deficiency (F. IX Def.)
- Data Provenance: Not explicitly stated regarding country of origin. The manufacturer is French (Diagnostica Stago, France), but the distributor is in the US (Diagnostica Stago, Inc., Parsippany, NJ). The plasma types suggest clinical samples, but whether they were collected retrospectively or prospectively, or from what geographic region, is not specified. It's common for such studies to use retrospectively collected samples from a clinical lab specializing in coagulation.
3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications:
This type of study does not involve "experts" establishing a ground truth in the sense of image interpretation or diagnostic classification. Instead, the "ground truth" for the test set is established by the measurement value provided by the predicate device (STA®-C.K.Prest® kit). The study compares the new device's readings to those of the predicate. Therefore, information about the number and qualifications of experts is not applicable here.
4. Adjudication Method for the Test Set:
Not applicable. There is no adjudication method described as this is a comparative analytical performance study, not a diagnostic accuracy study relying on human interpretation.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study:
No, an MRMC comparative effectiveness study was not done. This is an in-vitro diagnostic (IVD) device for laboratory testing, not an AI-powered diagnostic tool for human readers. Therefore, the concept of "human readers improving with AI vs. without AI assistance" does not apply.
6. Standalone Performance Study:
Yes, a standalone performance study was done implicitly. The STA®-Cephascreen Kit was used "exactly as described by their respective package inserts" to determine APTT values. The study then compared these standalone results to those obtained from the predicate device. The correlation data (r, a, b values) represent the analytical performance of the new device when used independently and compared to an established method.
7. Type of Ground Truth Used:
The "ground truth" for this study is the measurements obtained from the legally marketed predicate device, STA®-C.K.Prest® kit. The goal was to show that the new device produces results comparable to the predicate when measuring the same plasma samples. This is a common approach for demonstrating substantial equivalence for new IVD devices that perform the same function as existing ones.
8. Sample Size for the Training Set:
The document does not mention a "training set." This type of comparative analytical performance study for an IVD device does not typically involve machine learning or AI models requiring a training set in the conventional sense. The device is a reagent kit, not an algorithm that learns from data.
9. How Ground Truth for the Training Set Was Established:
Not applicable, as no training set is mentioned or implied for this type of IVD device study.
§ 864.7925 Partial thromboplastin time tests.
(a)
Identification. A partial thromboplastin time test is a device used for primary screening for coagulation abnormalities, for evaluation of the effect of therapy on procoagulant disorders, and as an assay for coagulation factor deficiencies of the intrinsic coagulation pathway.(b)
Classification. Class II (performance standards).