(49 days)
The Direct Bilirubin assay is used for the quantitation of direct bilirubin in human serum or plasma. Measurement of bilirubin, an organic compound formed during the normal and abnormal destruction of red blood cells, is used in the diagnosis and treatment of liver, hemolytic hematological, and metabolic disorders, including hepatitis and gall bladder block.
Direct Bilirubin is an in vitro diagnostic assay for the quantitative determination of direct bilirubin in human serum or plasma. The Direct Bilirubin assay is a clinical chemistry assay in which the conjugated bilirubin is oxidized to biliverdin. The resulting decrease in absorbance at 444 nm is directly proportional to the concentration of direct bilirubin.
Here's a breakdown of the acceptance criteria and study information for the DBil device, based on the provided text:
Acceptance Criteria and Device Performance
The device's performance was compared to a legally marketed predicate device, the Wako Diagnostics Direct Bilirubin assay on the Hitachi 717 Analyzer, to establish substantial equivalence.
| Acceptance Criteria (Predicate Performance) | Reported Device Performance (DBil) |
|---|---|
| Correlation Coefficient (vs. Predicate) | 0.9878 |
| Slope (vs. Predicate) | 1.168 |
| Y-intercept (vs. Predicate) | 0.081 mg/dL |
| Total %CV Level 1 | 4.0% |
| Total %CV Level 2 | 3.8% |
| Linearity | Up to 50.2 mg/dL |
| Limit of Quantitation (Sensitivity) | 0.11 mg/dL |
Note: The document doesn't explicitly state numerical acceptance criteria for correlation, slope, and y-intercept, but rather indicates that the "method comparison yielded acceptable correlation" and that the data "demonstrate that the performance...is substantially equivalent." The values provided are the reported performance of the DBil device during the comparative studies.
Study Information:
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Sample size used for the test set and the data provenance:
- Sample Size: Not explicitly stated. The document mentions "comparative performance studies" and "precision studies" conducted using "two levels of control material" (for precision) and "human serum or plasma" generally, but does not provide specific numbers of patient samples or the size of the test set used for method comparison.
- Data Provenance: Not specified (e.g., country of origin, retrospective or prospective).
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts: Not applicable. This is an in vitro diagnostic assay, and the "ground truth" for its performance is typically established through comparison to a well-characterized predicate device and through analytical performance studies (precision, linearity, sensitivity). Expert consensus for ground truth is not relevant in this context.
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Adjudication method (e.g. 2+1, 3+1, none) for the test set: Not applicable. See point 2.
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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 is not an AI-assisted diagnostic device, but a clinical chemistry assay.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done: The study evaluated the "Direct Bilirubin assay" which is an in vitro diagnostic test, performing in a standalone manner without human-in-the-loop performance influencing the assay's output. Its performance characteristics (correlation, precision, linearity, sensitivity) were measured intrinsically.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.): The "ground truth" for the device's performance was established through:
- Comparison to a legally marketed predicate device: The Wako Diagnostics Direct Bilirubin assay on the Hitachi 717 Analyzer served as the reference for comparative studies, with its established performance characteristics implicitly acting as a form of "ground truth" for substantial equivalence.
- Analytical performance metrics: Precision, linearity, and limit of quantitation (sensitivity) were determined experimentally for the DBil assay itself.
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The sample size for the training set: Not applicable. This is a chemical assay, not a machine learning or AI-based device, so there is no "training set" in the conventional sense.
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How the ground truth for the training set was established: Not applicable. There is no training set for this type of device.
§ 862.1110 Bilirubin (total or direct) test system.
(a)
Identification. A bilirubin (total or direct) test system is a device intended to measure the levels of bilirubin (total or direct) in plasma or serum. Measurements of the levels of bilirubin, an organic compound formed during the normal and abnormal distruction of red blood cells, if used in the diagnosis and treatment of liver, hemolytic hematological, and metabolic disorders, including hepatitis and gall bladder block.(b)
Classification. Class II.