(21 days)
The Direct Bilirubin assay is used for the quantitation of direct bilirubin in human serum or plasma. Measurements 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 reacts with diazotised sulphanilic acid to produce an acid azobilirubin, the absorbance of which is proportional to the concentration of direct bilirubin in the sample and can be measured at 550 nm.
The Abbott Laboratories Direct Bilirubin assay is an in vitro diagnostic assay intended for the quantitative determination of direct bilirubin in human serum or plasma. The device functions by reacting conjugated bilirubin with diazotized sulfanilic acid to produce an acid azobilirubin, the absorbance of which is proportional to the concentration of direct bilirubin in the sample and can be measured at 550 nm.
The study that proves the device meets the acceptance criteria is a comparative performance study against the predicate device, the Roche® Cobas Mira® Plus Automated Chemistry System Direct Bilirubin assay (K910593).
1. A table of acceptance criteria and the reported device performance:
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Correlation to Predicate Device | |
| Correlation Coefficient | 0.9969 |
| Slope | 1.199 |
| Y-intercept | 0.369 mg/dL |
| Precision | |
| Total %CV (Level 1/Panel 111) | 6.7% |
| Total %CV (Level 2/Panel 112) | 2.8% |
| Linearity (Assay Range) | Up to 16 mg/dL |
| Limit of Quantitation (Sensitivity) | 0.3 mg/dL |
Note: The document states "Both assays yield similar Performance Characteristics" and "The Direct Bilirubin assay method comparison yielded acceptable correlation with the Roche Cobas Mira Plus Automated Chemistry System Direct Bilirubin assay." The specific numerical acceptance criteria for correlation coefficient, slope, and y-intercept are not explicitly stated, but the reported values of 0.9969, 1.199, and 0.369 mg/dL respectively, are presented as acceptable for demonstrating substantial equivalence.
2. Sample size used for the test set and the data provenance:
- The document does not explicitly state the sample size used for the comparative performance studies (method comparison and precision studies).
- The data provenance (e.g., country of origin, retrospective or prospective) is not mentioned in the provided text.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This information is not applicable as the study design is a comparison to a predicate device, not a human expert-based ground truth establishment. The ground truth for this type of IVD is typically the analytical result from the predicate device or a reference method.
4. Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable for this type of analytical performance study. The comparison is objective, based on quantitative measurements.
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:
- This is not an MRMC comparative effectiveness study involving human readers or AI assistance. It is an analytical performance study of an in vitro diagnostic assay.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- This is a standalone diagnostic assay; its performance is evaluated based on its ability to quantitatively determine direct bilirubin, not in conjunction with human interpretation in the context of an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The "ground truth" for the comparative study was the results obtained from the predicate device, the Roche® Cobas Mira® Plus Automated Chemistry System Direct Bilirubin assay.
8. The sample size for the training set:
- This is an analytical performance study of a diagnostic assay, not a machine learning algorithm. Therefore, there is no "training set" in the context of AI/ML.
9. How the ground truth for the training set was established:
- Not applicable, as there is no "training set" for this type of diagnostic assay.
§ 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.