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For the in vitro quantitative determination of fibrin degradation products including D-Dimer and X-oligomers. In conjunction with a non-high clinical probability assessment, a normal (

The Tina-Quant® D-Dimer test system is an immunoturbidimetric assay for the in vitro quantitative determination of fibrin degradation products including D-Dimer and X-oligomers. Latex particles of uniform size are coated with monoclonal antibodies (F(ab')2 fragments) to the D-Dimer epitope. The antigen/antibody complexes produced by the addition of samples containing D-dimer lead to an increase in the turbidity of the test reactants, which can be determined turbidimetrically. The calibrator is D-Dimer calibrator and the recommended control material is D-dimer Control I/II.

Here's an analysis of the provided text regarding the Tina-Quant D-Dimer Test System, focusing on acceptance criteria and supporting studies:

1. Table of Acceptance Criteria and Reported Device Performance

Important Note: The provided text describes the results of the studies but does not explicitly state predefined acceptance criteria (e.g., "The device must achieve a sensitivity of at least 95%"). The phrase "excludes deep vein thrombosis (DVT) and pulmonary embolism (PE) with high sensitivity" implies that the reported values (99.3%, 99.4%, 0.6% for DVT and 100%, 100%, 0% for PE) met the internal criteria for "high sensitivity."

2. Sample Size Used for the Test Set and Data Provenance

• DVT Exclusion Study:
  • Sample Size: 812 outpatients with suspected DVT.
  • Data Provenance: Multicenter management study. The country of origin is not specified but is likely within regions where such clinical studies are conducted (e.g., North America, Europe) given the 510(k) submission to the FDA. The study is prospective in nature as patients were followed up for 3 months for development of DVT.
• PE Exclusion Study:
  • Sample Size: 168 outpatients with suspected PE.
  • Data Provenance: Management study. The country of origin is not specified. The study is prospective in nature as patients were followed up for 3 months for development of PE.

3. Number of Experts Used to Establish Ground Truth for the Test Set and Their Qualifications

The text does not provide information on the number of experts or their qualifications for establishing the ground truth for the DVT and PE diagnoses. The ground truth (development of DVT or PE) was determined by "further diagnostic testing" (for patients not excluded by D-Dimer and Wells score) and clinical follow-up over 3 months. This typically involves established medical diagnostic procedures and clinical outcomes, implicitly involving medical professionals, but specific details about expert panels are absent.

4. Adjudication Method for the Test Set

The text does not describe an explicit adjudication method (e.g., 2+1, 3+1 for discrepancies) for establishing the ground truth diagnoses of DVT or PE. The studies followed a management strategy:

• Patients with a non-high Wells score and a normal D-Dimer were not subjected to further diagnostic testing but were followed clinically for 3 months.
• Patients who did not meet these exclusion criteria presumably received standard diagnostic workups for DVT/PE which would establish the ground truth.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not performed. The studies described are management studies evaluating the performance of the Tina-Quant D-Dimer test in conjunction with clinical probability assessment (Wells score) for excluding DVT and PE, rather than comparing human reader performance with and without AI assistance. The device itself is an in vitro diagnostic (IVD) test, not an AI imaging or diagnostic algorithm designed to assist human readers.

6. If a Standalone (Algorithm Only Without Human-in-the-Loop Performance) Was Done

Yes, in a sense, the performance metrics reported (sensitivity, NPV, failure rate) reflect the standalone diagnostic utility of the D-Dimer test when used in conjunction with a clinical probability assessment. The "algorithm" here is the combined clinical probability assessment (Wells score) + D-Dimer cutoff. The reported outcomes (e.g., "Only one of 176 such patients developed DVT") are based on the result of this combined diagnostic strategy, where a particular result (non-high PTP + normal D-Dimer) leads to no further testing and a subsequent clinical follow-up. While there's a human in the loop for the Wells score assessment, the test itself has a standalone numerical result.

7. The Type of Ground Truth Used

The ground truth used was outcomes data / clinical diagnosis, specifically:

• For patients who were not excluded by the D-Dimer + Wells score, the ground truth for DVT/PE would likely be established by conventional diagnostic imaging (e.g., ultrasound for DVT, CTPA for PE).
• For the patients who were excluded (non-high PTP + normal D-Dimer), the ground truth was established by absence of clinical events (DVT/PE) during a 3-month follow-up period. The "failure rate" indicates how many of these excluded patients did develop the condition. This indicates that a combination of clinical outcomes and potentially further diagnostic testing was used for the entire study cohort.

8. Sample Size for the Training Set

The text does not provide information on a training set sample size. This is an in vitro diagnostic (IVD) device, which typically undergoes analytical validation (precision, accuracy, measuring range, etc.) and then clinical validation (as described here). The clinical studies presented are for validation/testing, not for training a machine learning model.

9. How the Ground Truth for the Training Set Was Established

As no training set is described for a machine learning context, this question is not applicable based on the provided text. The device is an immunoturbidimetric assay, not an AI/ML diagnostic.

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Immunoturbidimetric assay for the in vitro quantitative determination of fibrin degradation products including D-Dimer and X-oligomers in plasma.

The Tina-quant® D-Dimer Test system is a particle enhanced immunoturbidimetric assay. Latex particles are coated with monoclonal antibodies to the D-Dimer epitope. The antigen/antibody complexes produced by the addition of samples containing D-Dimer lead to an increase in turbidity.

This is a 510(k) summary for a D-Dimer test system, which is an in vitro diagnostic device. The provided text does not include the specific acceptance criteria or the study data proving the device meets those criteria. It focuses on the device's description, intended use, and substantial equivalence to a predicate device.

Therefore, I cannot provide the requested table of acceptance criteria and reported device performance, nor the details about the study design, sample sizes, expert involvement, and ground truth for a performance study.

The text does provide information in some of the other requested categories based on the context of a 510(k) submission for an in vitro diagnostic:

1. A table of acceptance criteria and the reported device performance:
* Not Available in the provided text. This information is typically found in the performance studies section of a 510(k) submission, detailing sensitivity, specificity, accuracy, precision, linearity, etc., and statistical results compared to pre-defined acceptance criteria.

2. Sample size used for the test set and the data provenance (e.g., country of origin of the data, retrospective or prospective):
* Not Available in the provided text.

3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g., radiologist with 10 years of experience):
* Not Applicable/Available in the provided text. For an in vitro diagnostic device like a D-Dimer test, "ground truth" for a test set would typically be established by a reference method (e.g., another established D-Dimer assay, or clinical outcome data if demonstrating clinical utility), rather than by human expert consensus in the way a medical imaging device might. The document does not mention details of the reference method used in any performance studies.

4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
* Not Applicable/Available in the provided text. Adjudication methods are typically used when human interpretation of data (e.g., images) forms part of the ground truth or comparison, which is not the case for this type of quantitative biochemical assay.

5. If a multi-reader multi-case (MRMC) comparative effectiveness study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance:
* Not Applicable. This device is an automated in vitro diagnostic assay, not an AI-assisted diagnostic tool requiring human reader interpretation in the context of MRMC studies.

6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
* Yes, by nature of the device. The Tina-quant® D-Dimer Test System is an automated immunoturbidimetric assay. Its performance is inherently standalone, as it provides quantitative results directly from a plasma sample without human interpretation of raw data beyond reading the numerical output. The "algorithm" in this context refers to the chemical and optical reactions and the instrument's processing of the turbidity changes.

7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
* Not explicitly stated in the provided text. For an in vitro diagnostic device like this, the "ground truth" in a validation study would typically be established by a well-characterized reference method or by clinical diagnosis/outcomes against which the D-Dimer levels are correlated.

8. The sample size for the training set:
* Not Applicable/Available in the provided text. This is an automated assay, not a machine learning or AI algorithm that requires a "training set" in the computational sense. The "development" of such an assay involves chemical formulation and calibration, not algorithm training on data.

9. How the ground truth for the training set was established:
* Not Applicable/Available in the provided text due to the nature of the device (see point 8).

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