(138 days)
The Diazyme Lp(a) is intended as a latex particle enhanced immunoturbidimetric assay for the in vitro quantitative determination of lipoprotein(a) [Lp(a)] concentration in human serum er plasma (EDTA) on Clinical Chemistry Systems. The measurement of Lp(a) is useful in evaluating lipid metabolism disorders and assessing atherosclerotic cardiovascular diseases in specific populations, when used in conjunction with clinical evaluation.
Diazyme Lp(a) Control is intended for use in monitoring the quality control of results obtained with the Diazyme Lp(a) reagents by turbidimetry.
Diazyme Lp(a) standard is intended for use in establishing the calibration curve for the Diazyme Lp(a) reagents by turbidimetry.
The Diazyme Lipoprotein (a) Assay is based on a latex enhanced immunoturbidimetric assay. Lp(a) in the sample binds to specific anti-Lp(a) antibody, which is coated on latex particles, and causes agglutination. The degree of the turbidity caused by agglutination can be measured optically and is proportional to the amount of Lp(a) in the sample.
Here's a breakdown of the acceptance criteria and the study details for the Diazyme Lp(a) Assay, based on the provided text:
Acceptance Criteria and Device Performance
The provided document describes the Diazyme Lp(a) Assay by comparing its performance to a predicate device (Denka Lp(a) Assay) and reporting specific performance characteristics such as precision and accuracy. The "acceptance criteria" are implied by the performance of the legally marketed predicate device and the new device demonstrating "good agreement" and "substantially similar" results.
| Acceptance Criterion (Implied by Predicate/Good Agreement) | Reported Diazyme Lp(a) Assay Performance |
|---|---|
| Reportable Range (Serum) | 5.44 mg/dL to 100.0 mg/dL (Predicate: 0.5mg/dL to 80.0 mg/dL) |
| Reportable Range (Plasma) | 5.44 mg/dL to 100.0 mg/dL (Predicate: 0.5mg/dL to 80.0 mg/dL) |
| Precision/Serum (Within Run) | 1.1% - 2.6% (Predicate: 1.26% - 2.00%) |
| Precision/Serum (Total) | 2.4% - 3.6% (Predicate: 0.99% - 2.22%) |
| Accuracy/Serum (Correlation Coefficient) | 0.998 (Predicate: 0.989) |
| Accuracy/Serum (Slope/Intercept) | y = 0.9895x + 0.0279 (Predicate: y = 1.108x - 1.44) |
| Accuracy/Plasma (Correlation Coefficient) | 0.9803 (Predicate: 0.990) |
| Accuracy/Plasma (Slope/Intercept) | y = 1.044x + 0.0407 (Predicate: y = 1.079x - 0.16) |
| Interference (Triglycerides) | Less than 10% interference at 1000 mg/dL |
| Interference (Ascorbic acid) | Less than 10% interference at 10 mmol/L |
| Interference (Bilirubin) | Less than 10% interference at 40 mg/dL |
| Interference (Bilirubin Conjugated) | Less than 10% interference at 40 mg/dL |
| Interference (Hemoglobin) | Less than 10% interference at 1000 mg/dL |
Note: The acceptance criteria are based on demonstrating "substantial equivalence" to the predicate device. This implies that the new device's performance should be comparable and within acceptable analytical limits, which are not explicitly defined as numerical thresholds beyond the reported performance metrics. The statement "good agreement with legally marketed assay" and "no significant deviation" act as the overarching acceptance criteria for accuracy.
Study Details
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Sample Size used for the test set and the data provenance:
- Test Set Sample Size:
- Accuracy (Correlation studies): 76 serum samples.
- Precision: Three levels of serum specimens. While not explicitly stating the number of unique patient samples, the study design involved testing these three levels with 2 runs per day, with duplicates, over 20 working days.
- Interference: Human serum samples were used, but the exact number is not specified.
- Data Provenance: Not explicitly stated, but the samples are "human serum" and "human plasma." There is no mention of country of origin or whether the data was retrospective or prospective.
- Test Set Sample Size:
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Number of experts used to establish the ground truth for the test set and the qualifications of those experts:
- This device is an in vitro diagnostic assay that quantifies a biomarker (Lp(a)). The "ground truth" for such assays is typically established by comparative methods, such as a legally marketed predicate device or a reference method. It does not involve human expert interpretation of images or clinical findings in the same way as, for example, a radiology AI device. Therefore, no information on human experts establishing ground truth for the test set or their qualifications is provided or relevant in this context.
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Adjudication method for the test set:
- Not applicable. As explained above, this is a quantitative diagnostic assay where the "ground truth" is typically the result from a reference method or predicate device, not subject to human expert adjudication. The comparison method is direct measurement against the predicate device.
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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:
- Not applicable. This is an in vitro diagnostic assay, not an AI-powered diagnostic imaging device that assists human readers. Therefore, an MRMC study and AI-assisted performance improvement are not relevant.
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If a standalone (i.e. algorithm only without human-in-the-loop performance) was done:
- Yes, this is primarily a standalone device performance study. The Diazyme Lp(a) Assay is an automated quantitative assay. The reported performance metrics (precision, accuracy, interference) are for the device itself operating without human interpretation of its primary output beyond standard laboratory procedures for running an assay. The comparison against the predicate device reflects the standalone performance.
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The type of ground truth used:
- The "ground truth" for the accuracy study was established by comparison with an existing commercial Lp(a) assay method (the predicate device, Denka Lp(a) Assay, K013359). This is a common method for establishing accuracy and substantial equivalence for in vitro diagnostic devices.
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The sample size for the training set:
- No information about a "training set" is provided. This is typical for in vitro diagnostic assays based on chemical/immunological reactions, as they are not machine-learning algorithms that require a training phase with labeled data in the same way an AI device does. The device's performance characteristics are determined through analytical validation studies (precision, accuracy, interference, linearity, etc.).
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How the ground truth for the training set was established:
- Not applicable, as no training set for an AI/machine learning algorithm is mentioned or relevant for this type of in vitro diagnostic device.
§ 866.5600 Low-density lipoprotein immunological test system.
(a)
Identification. A low-density lipoprotein immunological test system is a device that consists of the reagents used to measure by immunochemical techniques the low-density lipoprotein in serum and other body fluids. Measurement of low-density lipoprotein in serum may aid in the diagnosis of disorders of lipid (fat) metabolism and help to identify young persons at risk from cardiovascular diseases.(b)
Classification. Class II (performance standards).