(47 days)
The CHEM 2 CAL is an in vitro diagnostic product for the calibration of Phosphorus (PHOS), Salicylate (SAL), and Triglycerides (TRIG) methods on the Dimension Vista™ System.
CHEM 2 CAL is a liquid, multi-analyte, bovine serum albumin based product containing phosphorus, salicylate and glycerol. The kit consists of six vials, three vials of Calibrator A, and three vials of Calibrator B which are ready for use (no preparation is required). The volume per vial is 2.0 mL.
Here's an analysis of the acceptance criteria and study information for the Dimension Vista™ System Chemistry 2 Calibrator (CHEM 2 CAL - KC120), based on the provided text:
Acceptance Criteria and Device Performance
The primary performance characteristic detailed for the CHEM 2 CAL is its stability. The acceptance criterion for stability is a percent change over time less than or equal to 5% when comparing results of the product stored at 4°C with a control stored at -20°C.
| Acceptance Criteria | Reported Device Performance |
|---|---|
| Stability | |
| Shelf-life: % change ≤ 5% | Assignment at commercialization reflects real-time data on file, implying the 5% criterion is met. |
| On-board (punctured) stability: 7 days | Not explicitly stated if the 5% criterion was met for 7 days, but implies stability for this period. |
| Open vial (recapped, refrigerated) stability: 30 days | Not explicitly stated if the 5% criterion was met for 30 days, but implies stability for this period. |
| Traceability | Traceable to NIST SRM 2186I (PHOS), Sodium Salicylate ACS grade (SAL), Glycerol Anhydrous ACS grade (TRIG). |
| Bottle Value Assignment | Final bottle assignment for each commercial lot tested with N=45 replicates. |
Study Details
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Sample size used for the test set and the data provenance:
- Test set sample size: For "Bottle Value Assignment," N=45 replicates were tested for each level of the commercial lot.
- Data Provenance: The document does not explicitly state the country of origin or whether the data is retrospective or prospective. Given it's a submission to the FDA, the testing would likely be performed in a controlled laboratory environment, potentially in the US or at the manufacturer's facility (Dade Behring Inc., Newark, DE). The stability testing involves comparing current product results to controls, suggesting prospective testing over time.
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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 a calibrator, and its "ground truth" relates to its chemical composition and the assigned values. The ground truth (traceability) for constituent concentrations is established through reference materials and primary standards, not human expert consensus.
- PHOS: NIST SRM 2186I (National Institute of Standards and Technology - Standard Reference Material).
- SAL: Sodium Salicylate ACS grade (American Chemical Society).
- TRIG: Glycerol Anhydrous (ACS grade).
- The "experts" in this context would be the organizations defining these standards (NIST, ACS) and the analytical chemists performing the value assignments and verification using primary standards.
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Adjudication method (e.g., 2+1, 3+1, none) for the test set:
- Not applicable. Adjudication methods like 2+1 or 3+1 are typically used for subjective clinical assessments where multiple human readers interpret images or data. For a chemical calibrator, validation relies on objective analytical measurements against traceable standards.
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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 a chemical calibrator for in-vitro diagnostic instruments, not an AI-assisted diagnostic tool for human readers.
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If a standalone (i.e., algorithm only without human-in-the-loop performance) was done:
- Not applicable. This is a physical calibrator material, not an algorithm. The "performance" is its ability to accurately calibrate an instrument, which is an inherent property of the material and its assigned values. The instrument itself performs the analytical measurement in a standalone manner.
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The type of ground truth used (expert consensus, pathology, outcomes data, etc.):
- The ground truth for the calibrator's value assignments is based on traceability to internationally recognized chemical standards (NIST SRM, ACS grade materials) and verification using primary standards.
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The sample size for the training set:
- Not applicable. This is a physical calibrator, not a machine learning model that requires a training set. The "development" involves manufacturing to precise specifications and assigning values based on analytical measurements, not training an algorithm.
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How the ground truth for the training set was established:
- Not applicable, as there is no training set for this device. The chemical composition and value assignments are based on the manufacturing process and analytical validation against established chemical standards. The stock solution concentrations are "verified using an instrument calibrated with primary standards," and the final bottle assignments are tested against these.
§ 862.1150 Calibrator.
(a)
Identification. A calibrator is a device intended for medical purposes for use in a test system to establish points of reference that are used in the determination of values in the measurement of substances in human specimens. (See also § 862.2 in this part.)(b)
Classification. Class II (special controls). The device is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.