(57 days)
The Access DHEA-S assay is a paramagnetic particle, chemiluminescent immunoassay for the quantitative measurement of dehydroepiandrosterone sulfate levels in human serum and plasma using the Access Immunoassay Systems.
Measurement of dehydroepiandrosterone sulfate may be used in the differential diagnosis of Cushing's syndrome as well as in the evaluation of adrenocortical diseases, congenital adrenal hyperplasia, and adrenal tumors. In hirsute female patients, increased DHEA-S levels have been associated with virilizing adrenal tumors. Patients with polycystic ovary syndrome have often demonstrated elevated levels of DHEA-S, with persons overall androgen contribution to the defect in this disorder.
The Access DHEA-S Calibrators are intended to calibrate the Access DHEA-S assay for the quantitative determination of Dehydroepiandrosterone sulfate levels in human serum and plasma using the Access Immunoassay Systems.
The Access® DHEA-S Reagent is designed for optimal performance on the Access family of Immunoassay Systems, including the Access 2, UniCel Dxl and UniCel DxC Systems. The Access Immunoassay Systems utilize a competitive binding immunoassay for quantitative analyte measurement. The Access DHEA-S Reagent is packaged in two 50-test reagent packs and is packaged separately from the associated calibrators. The Access DHEA-S Calibrators are designed for use with the Access DHEA-S Reagent for generation of the Access calibration curve on Access Immunoassay Systems. The Access calibrators are packaged in 5.0 mL bottles, one for each of six calibrator levels.
Here's a breakdown of the acceptance criteria and study information for the Access® DHEA-S Reagent and Calibrators, based on the provided 510(k) summary:
1. Table of Acceptance Criteria and Reported Device Performance
The 510(k) summary does not explicitly state formal "acceptance criteria" with numerical targets for each performance parameter. Instead, it presents performance data and implies that these results were considered sufficient for substantial equivalence. The comparison is made against a legally marketed predicate device (Immulite DHEA-SO4 Reagent).
| Performance Measure | Acceptance Criteria (Implied) | Reported Device Performance (Access DHEA-S) | Predicate Device (Immulite DHEA-SO4) |
|---|---|---|---|
| Method Comparison | Strong correlation with predicate (r close to 1) and a slope close to 1 with minimal intercept. | Slope: 1.028 | N/A (predicate for comparison) |
| Intercept: 6.6 | N/A (predicate for comparison) | ||
| r (correlation coefficient): 0.993 | N/A (predicate for comparison) | ||
| Analytical Sensitivity | Performance comparable to or better than predicate. | 2 µg/dL | 3 µg/dL |
| Reportable Range | Performance comparable to or better than predicate. | 2 - 1000 µg/dL | 15-1000 µg/dL |
| Within-Run Imprecision | Low coefficient of variation (%C.V.) across different concentration levels. | Level 1 (10.3 µg/dL): 8.3% C.V. | Not explicitly stated for predicate in summary |
| Level 2 (34.4 µg/dL): 3.2% C.V. | |||
| Level 3 (123.9 µg/dL): 4.8% C.V. | |||
| Level 4 (347.3 µg/dL): 2.6% C.V. | |||
| Level 5 (736.1 µg/dL): 1.6% C.V. | |||
| Total Imprecision | Low coefficient of variation (%C.V.) across different concentration levels. | Level 1 (10.3 µg/dL): 11.3% C.V. | Not explicitly stated for predicate in summary |
| Level 2 (34.4 µg/dL): 5.1% C.V. | |||
| Level 3 (123.9 µg/dL): 6.4% C.V. | |||
| Level 4 (347.3 µg/dL): 4.4% C.V. | |||
| Level 5 (736.1 µg/dL): 3.7% C.V. |
2. Sample Size Used for the Test Set and Data Provenance
- Sample Size (Method Comparison): 263
- Data Provenance: Not explicitly stated in the summary (e.g., country of origin, retrospective or prospective). It is generally assumed that such studies for 510(k) submissions use prospectively collected samples or well-characterized retrospective samples.
- Sample Size (Imprecision): 80 for each of the 5 levels tested, for both within-run and total imprecision. The "N" column likely refers to the number of replicates or measurements performed for each level.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not applicable to this type of device (in vitro diagnostic for quantitative analyte measurement). The "ground truth" for chemical assays like this is typically established by reference methods or validated laboratory measurements, not by expert consensus or review of images.
4. Adjudication Method for the Test Set
This information is not applicable for this type of device. Adjudication methods (like 2+1, 3+1) are typically used in studies involving subjective interpretation, such as imaging studies, to resolve discrepancies between readers. This device measures a quantitative biochemical marker.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done, and the Effect Size of How Much Human Readers Improve with AI vs. Without AI Assistance
This information is not applicable to this device. This is an in vitro diagnostic assay, not an AI-based interpretation tool for human readers. Therefore, there are no "human readers" to improve with AI assistance in the context of this submission.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done
This information is not applicable in the AI sense. The device itself is a standalone assay system (reagent and calibrators used with an automated analyzer). Its performance is evaluated independently of human interpretation, but it's not an "algorithm" in the modern AI sense.
7. The Type of Ground Truth Used
For method comparison, the "ground truth" or reference values were generated by the predicate device (Immulite DHEA-SO4 Assay). For imprecision, the "ground truth" is derived from statistical analysis of repeated measurements of known concentration levels. It is based on analytical measurements of DHEA-S levels.
8. The Sample Size for the Training Set
The 510(k) summary does not specify a separate "training set" sample size. For an IVD like this, validation studies typically involve a single test set to demonstrate performance characteristics such as method comparison, linearity, and imprecision. While reagent formulation and assay development would involve internal optimization, it is not referred to as a "training set" in the context of this regulatory submission, nor are its details typically provided for the public summary.
9. How the Ground Truth for the Training Set Was Established
Since a "training set" is not explicitly mentioned or relevant in the context of this 510(k) summary for an IVD, the ground truth establishment for it is not described. For the performance evaluation that is reported, the ground truth is established by either the predicate device (for method comparison) or by repeated measurements of known samples (for imprecision).
§ 862.1245 Dehydroepiandrosterone (free and sulfate) test system.
(a)
Identification. A dehydroepiandrosterone (free and sulfate) test system is a device intended to measure dehydroepiandrosterone (DHEA) and its sulfate in urine, serum, plasma, and amniotic fluid. Dehydroepiandrosterone measurements are used in the diagnosis and treatment of DHEA-secreting adrenal carcinomas.(b)
Classification. Class I (general controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to § 862.9.