(23 days)
The intended use for the N-ASSAY L D-BIL Reagent is for the quantitative measurement of direct bilirubin in human serum in the diagnosis and treatment of various liver diseases. For in vitro diagnostic use only.
The N-ASSAY L D-BIL reagent is based on a chemical oxidation method, utilizing sodium nitrite as an oxidizing agent, shows good correlation with similar direct bilirubin reagents, practically no interference by coexistent substances, high sensitivity with good reproducibility, wide assay range, and is convenient ready-to-use liquid type reagent. In this method, a serum sample containing direct bilirubin is mixed with the reagent containing sodium nitrite. Direct billrubin is oxidized by nitrite at pH 3.7 to produce biliverdin which causes the absorbance at 450 nm (main) and 546 (sub), specific to bilirubin, to decrease. Therefore, the direct bilirubin concentration in the sample can be obtained by measuring the absorbance before and after the sodium nitrite oxidation.
Here's a breakdown of the acceptance criteria and study information for the N-ASSAY L D-BIL (Direct Bilirubin Assay Reagent), based on the provided text:
Acceptance Criteria and Device Performance
| Acceptance Criteria Category | Acceptance Criteria | Reported Device Performance |
|---|---|---|
| Correlation with Predicate | Not explicitly stated as a numerical AC, but generally implies a strong linear relationship. | Correlation coefficient of 0.98476 with predicate assay (WAKO Chemicals Direct Bilirubin liquid reagent). Regression equation: y = 1.0882 x + 0.1574. |
| Precision | Acceptable precision. | Precision studies indicate acceptable values can be obtained on a day-to-day basis. |
| Minimum Detectable Level | Not explicitly stated as a numerical AC. | Minimum detectable level of 0.05 mg/dl. |
| Linearity | Not explicitly stated as a numerical AC. | Linear to 20 mg/dl. |
| Interference by Coexistent Substances | Practically no interference by coexistent substances. | Shows practically no interference by coexistent substances. |
| Reagent Stability | Good reagent stability. | Good reagent stability. |
| Sensitivity | High sensitivity. | Shows high sensitivity. |
| Reproducibility | Good reproducibility. | Shows good reproducibility. |
| Assay Range | Wide assay range. | Shows wide assay range. |
| Convenience | Convenient ready-to-use liquid type reagent. | Is convenient ready-to-use liquid type reagent. |
Study Details
2. Sample size used for the test set and the data provenance:
- Sample Size: Not explicitly stated. The text mentions "serum samples" for the correlation study but doesn't provide the number of samples.
- Data Provenance: Not explicitly stated. Given it's a 510(k) submission for a diagnostic device, the samples would typically be human serum. It's not specified if they were retrospective or prospective, nor their country of origin.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- Not applicable. This is not a study requiring expert interpretation of images or other qualitative data. The comparison is against a legally marketed predicate device using quantitative measurements.
4. Adjudication method for the test set:
- Not applicable. This is not a study requiring adjudication of expert opinions. The comparison is analytical performance against a predicate device.
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:
- No. This is a 510(k) submission for an in vitro diagnostic reagent, not an AI-based imaging or analytical device that would involve human readers or AI assistance in interpretation.
6. If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Yes, implicitly. The performance metrics (correlation, precision, minimum detectable level, linearity) describe the analytical performance of the N-ASSAY L D-BIL reagent itself, without human intervention in the measurement process after sample introduction. It's a "device only" performance assessment.
7. The type of ground truth used:
- The "ground truth" for the comparison study was the measurements obtained from the predicate device, the WAKO Chemicals Direct Bilirubin liquid reagent (K970986). The study aimed to demonstrate substantial equivalence by correlating the new device's results with the predicate's results.
8. The sample size for the training set:
- Not applicable. This is a chemical reagent, not an algorithm that requires a training set in the sense of machine learning. The "development" would involve chemical formulation and optimization, not data training.
9. How the ground truth for the training set was established:
- Not applicable, as there's no training set in the context of an algorithm.
§ 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.