Search Results

The Tina-quant® Myoglobin Assay is an immunoturbidometric assay for the quantitative determination of Myoglobin in serum and plasma using automated clinical chemistry analyzers. Measurement of myoglobin aids in the rapid diagnosis of heart and renal disease.

The myoglobin determination is based upon turbidimetric immunoinhibition (TINIA) using a serum or plasma blood sample. The sample containing myoglobin is transferred into a EDTA/glycine buffer solution (R1 reagent). In the second step, an aliquot of solution containing fine latex particles coated with polyclonal anti-human myoglobin antibodies (R2 reagent) is added to mixture of the first step. The antibody-coated particles will bind to the myoglobin in the sample to form "aggregates" such that the amount of aggregate formed is proportionate to the amount of myoglobin present in the sample. The resulting agglutination complex is measured turbidimetrically whereby increased turbidity is reflected through an increase in optical density. Therefore, the amount of myoglobin in the sample is directly proportional to the amount of turbidity formed.

This document describes the Boehringer Mannheim Tina-quant® Myoglobin Assay, an immunoturbidometric assay for the quantitative determination of Myoglobin in serum and plasma. The study presented aims to demonstrate substantial equivalence to a predicate device, the Behring N Latex Myoglobin Assay.

Here's an analysis of the provided information regarding acceptance criteria and the supporting study:

1. Table of Acceptance Criteria and Reported Device Performance

The document does not explicitly state formal "acceptance criteria" but rather presents a comparison of performance characteristics between the subject device (Tina-quant® Myoglobin) and its predicate (N Latex Myoglobin). The implication is that performance comparable to or better than the predicate device constitutes acceptable performance.

Notes on the table:

• The units for Myoglobin are inconsistent between the provided predicate data (µg/L) and the subject device data (ng/mL) for precision, detection limit, and linearity. It's assumed 1 µg/L = 1 ng/mL for direct comparison in this table based on typical clinical ranges, but this is a critical point that would require clarification for a full regulatory assessment. For instance, the Tina-quant's detection limit of 3.0 ng/mL is significantly lower (better) than the N Latex's 25 µg/L, assuming equivalence of ng/mL and µg/L.
• The "Acceptance Criteria" column is derived from the reported performance of the predicate device. The study aims to show that the Tina-quant® Myoglobin performs comparably or better.

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

• Precision Test Set Sample Sizes:
  • Intra-Assay: 20 samples per control level (Control 1, Control 2, Control 3).
  • Inter-Assay: 20 samples per control level (Sample 1, Sample 2).
• Method Comparison Test Set Sample Size: N=41 samples.
• Data Provenance: The document does not explicitly state the country of origin or whether the data is retrospective or prospective. It is a 510(k) submission from 1997, so it's likely the data was generated specifically for this submission (prospective) and likely from studies conducted by Boehringer Mannheim or their contractors, though the location is not specified.

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

This type of information is not applicable to this study. The device is an in-vitro diagnostic (IVD) assay that measures a biomarker (Myoglobin) quantitatively. The "ground truth" for the test set is established by the reference method or the predicate device itself (for method comparison), not by expert consensus in interpreting images or clinical cases.

4. Adjudication Method for the Test Set

This is not applicable as there is no expert adjudication involved in determining the "truth" for quantitative biomarker measurements. The accuracy is assessed by comparing results to a reference method or predicate device, or by evaluating reproducibility.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was Done

No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is relevant for diagnostic imaging interpretation devices where human readers interpret cases with and without AI assistance. This document describes an IVD assay, not an imaging device.

6. If a Standalone (i.e. algorithm only without human-in-the loop performance) was Done

Yes, the performance presented for the Tina-quant® Myoglobin Assay is inherently standalone. It describes the analytical performance of the assay itself (precision, detection limit, linearity, interference, specificity) and its correlation with a predicate device, without any human-in-the-loop steps being part of the primary performance evaluation. The device functions as an automated quantitative measurement system on clinical chemistry analyzers.

7. The Type of Ground Truth Used

• For precision and linearity studies, the "ground truth" is typically established by using quality control materials (e.g., control 1, 2, 3 listed for precision) or spiked samples with known concentrations.
• For method comparison, the "ground truth" for the comparison itself is the predicate method/device (N Latex Myoglobin Assay) or, as implied for the predicate itself, a radioimmunnoassay (RIA) Myoglobin. The document states that the Tina-quant® was compared "Vs N Latex® Myoglobin" and the N Latex Myoglobin was compared "Vs Radioimmunnoassay Myoglobin." This suggests the RNA assay served as a previous reference standard.
• For interfering substances and specificity, the "ground truth" is based on controlled experiments where known amounts of the interfering substance or cross-reacting substance are added to samples, and the assay's response is measured against expected values.

8. The Sample Size for the Training Set

The document does not provide information regarding a training set sample size. This is common for traditional IVD assays, where the "model" (the assay chemistry and principles) is established through biochemical and analytical development, not typically through machine learning "training" on a data set in the same way an AI algorithm would be. The development of the assay chemistry relies on understanding biological interactions rather than statistical learning from a large dataset.

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

As there is no explicit "training set" in the context of an AI/ML algorithm, the ground truth establishment method for a training set is not applicable. The underlying principles of the Tina-quant® Myoglobin Assay are based on established immunoturbidimetric methods, which are developed and optimized through chemical and biological experiments, not data-driven machine learning training.

Ask a specific question about this device