(190 days)
The IMMULITE® Free PSA Calibration Material (CVM) is intended for monitoring system performance of the IMMULITE Immunoassay system for the quantitative measurement of Free PSA antigen.
IMMULITE® 2000 Free PSA Calibration Verification Material (CVM) contains one set of four vials (LPFCVM1-4), 2 mL each. LPFCVM1 contains bovine protein/buffer matrix with preservatives. LPFCVM2, LPFCVM3 and LPFCVM4 contain low, intermediate and high levels of Free PSA respectively, in human-source matrix with preservatives. The CVMs are supplied lyophilized form.
This document describes the IMMULITE® 2000 Free PSA Calibration Verification Material (CVM) and the performance testing conducted to demonstrate its substantial equivalence to a predicate device.
1. Table of Acceptance Criteria and Reported Device Performance
The device's performance is demonstrated through its stability testing. The acceptance criteria for stability state that the dose concentration for the stability CVM must be within ±10% of the assigned dose concentration. The study reports that acceptable results were observed, confirming it meets these criteria.
| CVM Level | Assigned Dose (ng free PSA/mL) | Acceptance Criteria (% difference to assigned dose) | Acceptable Range (ng free PSA/mL) | Reported Performance (meets criteria?) |
|---|---|---|---|---|
| LPFCVM1 | 0.00 | N/A | N/A | N/A (not applicable for 0.00 dose) |
| LPFCVM2 | 0.20 | +10% | 0.18 - 0.22 | Yes (reported as "acceptable results") |
| LPFCVM3 | 1.45 | +10% | 1.31 - 1.60 | Yes (reported as "acceptable results") |
| LPFCVM4 | 24.40 | +10% | 21.96 - 26.84 | Yes (reported as "acceptable results") |
2. Sample Size Used for the Test Set and Data Provenance
The "test set" in this context refers to the samples used for the stability study and value assignment, as this device itself is a calibration verification material and not a diagnostic test with a patient-based test set.
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Stability Study (test set for CVM stability):
- Sample Size: "CVM lot 15," "lots 90 and 91." Specific numbers of vials/samples are not provided, but it states CVMs are run "in duplicate (as a minimum)."
- Data Provenance: Not specified, but implied to be from Siemens' internal testing. It's a prospective study for stability monitoring.
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Value Assignment Validation (part of the device's performance characterization):
- Sample Size:
- 3 levels of commercially available controls.
- 20 normal male patient samples.
- 10 spiked samples.
- 10 PSA patient samples.
- Data Provenance: Not specified, but implied to be from Siemens' internal testing. Retrospective or prospective nature not explicitly stated, but typically these are prospective studies for product development.
- Sample Size:
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
Not applicable. The ground truth for this device (a calibration verification material) is established through traceability to a recognized standard (WHO 15 NIBSC IS (96/668)) and internal gravimetric preparation of reference calibrators, not through expert consensus on medical images or clinical outcomes.
4. Adjudication Method for the Test Set
Not applicable. This is not a diagnostic device requiring adjudication of results from different readers or interpretations. The performance is assessed against quantitative analytical criteria.
5. 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 device is a calibration verification material for an immunoassay system, not an AI-assisted diagnostic tool or a device that involves human readers interpreting cases.
6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) was done
Not applicable. This is a laboratory reagent, not an algorithm. Its "standalone performance" is its ability to maintain its assigned concentration over time, which is what the stability study assesses.
7. The Type of Ground Truth Used
The ground truth for the IMMULITE® 2000 Free PSA CVM is established through:
- Traceability to Reference Standard: The CVMs are traceable to WHO 15 NIBSC IS (96/668).
- Gravimetric Preparation: The assigned reference calibrators, from which the CVMs are derived, are prepared using Free PSA antigen stock and traceable to internal material that has been gravimetrically prepared.
- Value Assignment: CVM values are determined by running the CVMs in replicates on multiple instruments using reference internal calibration curves.
8. The Sample Size for the Training Set
Similar to "test set" described above, in the context of calibration verification materials, the concept of a "training set" doesn't directly apply as it would for an AI algorithm. However, for the initial value assignment of the CVM levels, which could be considered analogous to establishing "reference" data:
- CVM Level Testing: The Free PSA CVM levels were tested on 18 replicates in total, comprised of 6 runs and 3 replicates per run, on 4 IMMULITE 2000 system analyzers and 2 different reagent kit lots.
9. How the Ground Truth for the Training Set Was Established
The "ground truth" (the assigned values and ranges for the CVMs) was established as follows:
- Primary Traceability: Traceable to WHO 15 NIBSC IS (96/668).
- Internal Reference: Using internal material which has been gravimetrically prepared.
- Comprehensive Testing: The Free PSA CVMs are a subset of 11-level Free PSA calibrators. These calibrators and CVMs are value assigned using assigned reference calibrators. The CVM values are calculated based on recovered values from 18 replicates run on 4 different IMMULITE 2000 system analyzers with 2 different reagent kit lots. The values are then averaged across all systems.
- Validation: The CVM value assignments were validated using 3 levels of commercially available controls, 20 normal male patient samples, 10 spiked samples, and 10 PSA patient samples.
- Guideline Range: The Guideline Range (95% confidence interval) for each CVM level was established based on the Target Mean and ± 2 Standard Deviation (SD) from the collected data.
§ 862.1660 Quality control material (assayed and unassayed).
(a)
Identification. A quality control material (assayed and unassayed) for clinical chemistry is a device intended for medical purposes for use in a test system to estimate test precision and to detect systematic analytical deviations that may arise from reagent or analytical instrument variation. A quality control material (assayed and unassayed) may be used for proficiency testing in interlaboratory surveys. This generic type of device includes controls (assayed and unassayed) for blood gases, electrolytes, enzymes, multianalytes (all kinds), single (specified) analytes, or urinalysis controls.(b)
Classification. Class I (general controls). Except when intended for use in donor screening tests, quality control materials (assayed and unassayed) are exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.