(71 days)
The Nichols Advantage® Cortisol assay is intended for use with the Nichols Advantage® Specialty System for the quantitative determination of cortisol concentrations in human serum, EDTA plasma and urine. Measurements of cortisol are used in the diagnosis and treatment of disorders of the adrenal gland.
The Nichols Advantage Cortisol Assay Calibrators are intended for adjustment of the stored curve for the Nichols Advantage Cortisol assay.
The Nichols Advantage Cortisol assay contains sufficient reagents for 100 tests. The assay is a chemiluminescent competitive binding assay for cortisol in human serum, plasma, and urine.
Here's a breakdown of the acceptance criteria and study information for the Nichols Advantage® Cortisol assay, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The document doesn't explicitly state "acceptance criteria" in a formal, quantifiable manner for the overall device's performance. Instead, it compares the performance characteristics of the new device (Nichols Advantage Cortisol) to a predicate device (DPC Coat-A-Count Cortisol RIA). The implicit acceptance criterion appears to be "substantial equivalence" to the predicate device across various performance metrics.
| Feature | Predicate Device (DPC Coat-A-Count Cortisol) | New Device (Nichols Advantage Cortisol) | Comparison/Acceptance Status |
|---|---|---|---|
| Method Comparison | |||
| Pearson's r | Not applicable | 0.97 | Considered good correlation |
| Deming Regression | Not applicable | Y = 0.70X + 2.5 | Considered equivalent |
| Range (Method X) | 1.9 to 68.2 µg/dL | Not applicable | |
| Range (Method Y) | Not applicable | 2.8 to 49.5 µg/dL | |
| Performance Characteristics | |||
| Within-Run Precision (%CV) | 3.0-5.1% | 3.6-8.7% | Comparable |
| Total Precision (%CV) | 4.0-6.4% | 7.1-17.4% | Comparable |
| Recovery | 91-100% | 97-109% | Comparable |
| Linearity | 92-101% | 94-107% | Comparable |
| Analytical Sensitivity | 0.2 µg/dL | ≤0.8 µg/dL | Comparable |
Note: The conclusion states: "These data... demonstrate safety and effectiveness of the Nichols Advantage Cortisol for its intended in vitro diagnostic use. Furthermore, based on performance characteristics, the Nichols Advantage Cortisol assay is substantially equivalent to the predicate method." This implies the reported performance values fell within acceptable limits relative to the predicate device for FDA clearance.
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size: 150 serum samples
- Data Provenance: The document states the samples were "human serum samples in which the clinical diagnosis were unknown." It does not specify the country of origin. Given the manufacturer's address in San Clemente, CA, United States, it's reasonable to infer a U.S. origin, though not explicitly stated. The study appears to be retrospective as it uses existing "serum samples."
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Their Qualifications
The document does not mention the use of experts to establish ground truth for the test set. The comparison is made against a legally marketed predicate device, where the predicate device's results serve as the reference for comparison.
4. Adjudication Method for the Test Set
Not applicable. There was no mention of an adjudication process as the comparison was against a predicate device's quantitative measurements.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done
No, an MRMC comparative effectiveness study was not done. This study focuses on the analytical performance of an in vitro diagnostic assay, comparing it to an existing assay, rather than assessing human reader performance.
6. If a Standalone Study Was Done
Yes, a standalone study was performed to characterize the performance of the Nichols Advantage Cortisol assay on its own (e.g., within-run precision, total precision, recovery, linearity, analytical sensitivity). The results of these intrinsic performance metrics are reported in the "Comparison of Performance Characteristics" table.
7. The Type of Ground Truth Used
The "ground truth" for the comparative study was the results obtained from the predicate device, DPC Coat-A-Count Cortisol RIA. This is a common approach for demonstrating substantial equivalence for in vitro diagnostic assays.
8. The Sample Size for the Training Set
The document does not provide information about a separate "training set" or its size. In the context of IVD assays like this, the "development" or "training" might involve internal validation and optimization, but specific training set sizes are not typically reported in 510(k) summaries for device performance. The reported study of 150 samples appears to be the primary validation data.
9. How the Ground Truth for the Training Set Was Established
As no specific training set is mentioned, the method for establishing its ground truth is also not described. If there was an internal development phase, the ground truth for any optimization would likely be established in a similar manner to the reported comparison study (i.e., comparison to established methods or reference standards).
§ 862.1205 Cortisol (hydrocortisone and hydroxycorticosterone) test system.
(a)
Identification. A cortisol (hydrocortisone and hydroxycorticosterone) test system is a device intended to measure the cortisol hormones secreted by the adrenal gland in plasma and urine. Measurements of cortisol are used in the diagnosis and treatment of disorders of the adrenal gland.(b)
Classification. Class II.