(73 days)
The AHDL method for the Dimension® clinical chemistry system is a device used to quantitatively measure High Density Lipoprotein Cholesterol in human serum or plasma. AHDL measurements are used as an aid in the diagnosis and treatment of lipid disorders.
The AHDL method for the Dimension® clinical chemistry system is a homogeneous method for direct measurement of high density lipoprotein (HDL) cholesterol levels without the need for off-line pretreatment or centrifugation steps. The method is in a two-reagent format and depends on the properties of a unique detergent, which solubilizes only the HDL particles, thus releasing HDL cholesterol to react with cholesterol esterase to produce color. In addition to selectively disrupting the HDL particles, this detergent also inhibits the reaction of the cholesterol enzymes with LDL, VLDL and chylomicrons by adsorbing to their surfaces. A polyanion is contained in the first reagent to assist with complexing LDL, VLDL and chylomicrons, further enhancing the selectivity of the detergent and enzymes for HDL cholesterol.
Here's an analysis of the acceptance criteria and the study proving the device meets them, based on the provided text:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly state "acceptance criteria" for the new device. Instead, it demonstrates substantial equivalence to a predicate device. The performance is assessed through a split-sample comparison, with the implicit criterion being a strong correlation and acceptable agreement between the new device and the predicate.
| Acceptance Criterion (Implicit) | Reported Device Performance (vs. Predicate) |
|---|---|
| Strong correlation coefficient | 0.991 |
| Slope close to 1.0 | 0.931 |
| Intercept close to 0.0 mg/dL | 0.811 mg/dL |
2. Sample Size and Data Provenance for the Test Set
- Sample Size: 272 clinical patient samples.
- Data Provenance: The document does not specify the country of origin. It states "clinical patient samples," implying they were collected from patients. It's a retrospective comparison against existing samples analyzed by the predicate device.
3. Number of Experts and Qualifications for Ground Truth
Not applicable. This study does not involve expert readers establishing ground truth for images or interpretations. It's a quantitative measurement device comparison where the predicate device's results serve as the comparison baseline.
4. Adjudication Method for the Test Set
Not applicable. There's no adjudication needed as it's a direct comparison of quantitative measurements from two analytical methods on the same samples.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is typically used for diagnostic imaging devices where human interpretation is involved. The Dimension® AHDL is an automated quantitative measurement device.
6. Standalone Performance Study
Yes, a standalone performance study of the new device relative to the predicate device was conducted. The "split-sample comparison" essentially serves as the standalone performance assessment of the new device's quantitative output. While it's compared to another device, the core functionality of the AHDL system is evaluated on its own merits for linearity, correlation, and agreement within the context of substantial equivalence.
7. Type of Ground Truth Used
The "ground truth" for the comparison was the results obtained from the predicate device (Dimension® HDL Assay). The study aimed to demonstrate that the new device's measurements were substantially equivalent to those of a previously approved method. While the predicate device's results are not considered absolute "ground truth" in the pathological sense, they serve as the acceptable reference standard for this type of equivalence claim.
8. Sample Size for the Training Set
The document does not mention a "training set" in the context of machine learning or AI. This is a chemical assay, and its development would involve method optimization and validation rather than a training set for an algorithm.
9. How the Ground Truth for the Training Set Was Established
Not applicable, as there is no mention of a training set or AI algorithm in this context. The method's performance characteristics (e.g., reagent formulation, reaction kinetics) would be established through laboratory experiments and verification against known standards and other established methods.
§ 862.1475 Lipoprotein test system.
(a)
Identification. A lipoprotein test system is a device intended to measure lipoprotein in serum and plasma. Lipoprotein measurements are used in the diagnosis and treatment of lipid disorders (such as diabetes mellitus), atherosclerosis, and various liver and renal diseases.(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.