(19 days)
The intended use for the N-ASSAY L T-BIL Reagent is for the quantitative determination of serum Total Bilirubin in the diagnosis and treatment of various liver diseases. For in vitro diagnostic use only.
The N-ASSAY L T-BIL reagent is based on a chemical oxidation method, utilizing sodium nitrite as an oxidizing agent, shows good correlation with similar Total 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 total bilirubin is mixed with the reagent containing sodium nitrite. Total bilirubin (direct bilirubin) 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 total billinubin concentration in the sample can be obtained by measuring the absorbance before and after the sodium nitrite oxidation.
Acceptance Criteria and Study for Crestat N-ASSAY L T-BIL Reagent
This medical device is a diagnostic reagent for measuring total bilirubin. The provided text describes a 510(k) submission, focusing on establishing substantial equivalence to a predicate device.
1. Table of Acceptance Criteria and Reported Device Performance
The provided document does not explicitly state pre-defined acceptance criteria values in the format of a typical performance goal. Instead, the study aims to demonstrate substantial equivalence to a predicate device. The performance metrics reported are for comparison to this predicate.
| Performance Metric | Acceptance Criteria (Implied by Substantial Equivalence) | Reported Device Performance |
|---|---|---|
| Correlation Coefficient (vs. Predicate) | High correlation (e.g., >0.95 or >0.98) | 0.99922 |
| Regression Equation (vs. Predicate) | Close to y = x (slope ~1, intercept ~0) | y = 1.0166 x + 0.1192 |
| Precision | Acceptable (qualitative statement) | "acceptable values can be obtained on a day to day basis" |
| Minimum Detectable Level | Comparable to predicate / clinically acceptable | 0.05 mg/dl |
| Linearity | Comparable to predicate / clinically acceptable | Linear to 50 mg/dl |
| Interference by Coexistent Substances | Practically no interference | "practically no interference by coexistent substances" |
| Reproducibility | Good reproducibility | "good reproducibility" |
| Sensitivity | High sensitivity | "high sensitivity" |
| Assay Range | Wide assay range | "wide assay range" |
Note: The "acceptance criteria" are inferred based on demonstrating substantial equivalence, meaning the performance should be very similar to or better than the predicate's known performance.
2. Sample Size and Data Provenance
- Test Set Sample Size: Not explicitly stated. The text mentions "serum samples" were used in comparison studies against the predicate.
- Data Provenance: Not explicitly stated. Given it's a 510(k) from 1998 in the US, it's highly likely the data was collected in the US. It's also typical for such studies to be prospective, but this is not explicitly stated.
3. Number of Experts and Qualifications for Ground Truth
Not applicable. The ground truth for this type of in vitro diagnostic device is typically established against a reference method or by comparison to a legally marketed predicate device, rather than expert consensus on individual cases.
4. Adjudication Method
Not applicable. No expert adjudication method is described as the study focuses on quantitative measurement and comparison to a predicate device.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No. This is an in vitro diagnostic (IVD) reagent, and MRMC studies are typically performed for imaging or qualitative diagnostic devices where human interpretation is a key component. The effectiveness study here is based on quantitative analytical performance against a predicate.
6. Standalone Performance Study
Yes, the analytical performance (correlation coefficient, regression equation, precision, minimum detectable level, linearity, interference, reproducibility, sensitivity, assay range) of the N-ASSAY L T-BIL reagent was evaluated on its own and compared to the predicate device. This constitutes a standalone performance evaluation in the context of IVD reagents.
7. Type of Ground Truth Used
The ground truth was established by comparison to a legally marketed predicate device, specifically the WAKO Chemicals Total Bilirubin liquid reagent (K970985). This predicate device serves as the "reference standard" against which the new device's performance is measured to demonstrate substantial equivalence.
8. Sample Size for the Training Set
Not applicable. This is an analytical device for measuring a biochemical marker. There is no "training set" in the machine learning sense. The device's performance is determined by its chemical reagents and reaction principles, which are developed through R&D, not by training on a dataset.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no training set mentioned or implied 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.