(47 days)
Liquichek Urine Toxicology Controls are intended for use as quality controls urine to monitor the performance of laboratory urine toxicology screening* procedures. *[S1E/S2E: enzyme immunoassay (EIA)]
Levels S1, S2, S3, S1 Low Opiate, and S2 Low Opiate: Liquichek Urine Toxicology Control is intended for use as a quality control urine to monitor the performance of laboratory urine toxicology screening procedures.
Levels S1E, S2E, S1E Low Opiate and S2E Low Opiate: Liquichek Urine Toxicology Control is intended for use as a quality control urine to monitor the performance of laboratory urine toxicology enzyme immunoassay (EIA) screening procedures.
Liquichek Urine Toxicology Controls are prepared from human urine with added drugs of abuse and metabolites of drugs of abuse, preservatives, stabilizers and constituents of animal origin. The control is provided in liquid form for convenience.
The provided document focuses on the substantial equivalence of the "Liquichek Urine Toxicology Control (Screen Series)" device to an already marketed predicate device (K021411). The performance data presented are related to the stability of the control material rather than the diagnostic accuracy of a new testing algorithm or method.
Therefore, many of the typical questions regarding acceptance criteria and studies for diagnostic devices (like sample size, ground truth, expert adjudication, MRMC studies, or standalone algorithm performance) are not applicable in this context. This device is a control material used to monitor the performance of other urine toxicology screening procedures, not a screening procedure itself.
Here's an analysis based on the information provided, recognizing the nature of the device:
1. Table of Acceptance Criteria and Reported Device Performance
| Acceptance Criteria (related to device stability) | Reported Device Performance |
|---|---|
| Open Vial Stability: All analytes stable for 30 days when stored tightly capped at 2-8°C. | All analytes are stable for 30 days when stored tightly capped at 2-8°C. |
| Shelf Life (S1E, S2E, S1E Low Opiate, S2E Low Opiate): Two years stored at 2-8°C. | Two years stored at 2-8°C. |
| Shelf Life (S1, S2, S3, S1 Low Opiate, S2 Low Opiate): Three years stored at 2-8°C. | Three years stored at 2-8°C. |
2. Sample size used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document does not specify a "test set" in the context of diagnostic accuracy. The studies performed were stability studies on the control material itself. The sample size for these studies is not explicitly stated (e.g., how many vials, how many batches were tested). The provenance of the data is implied to be Bio-Rad Laboratories in Irvine, California, USA, the submitter of the device, making it prospective for the purpose of demonstrating stability.
3. Number of experts used to establish the ground truth for the test set and the qualifications of those experts (e.g. radiologist with 10 years of experience)
Not applicable. This device is a quality control material, not a diagnostic test that requires expert interpretation for ground truth. The "ground truth" for this device would be its certified concentrations of drugs/metabolites, which are inherently known during its manufacture.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. Adjudication methods are used to resolve discrepancies in expert interpretation of diagnostic results, which is not relevant for a control material's stability study.
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. MRMC studies are for evaluating the performance of diagnostic tools (often involving human readers or AI algorithms) on patient cases. This device is a control product.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This device is a quality control material, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
For the stability studies, the "ground truth" is the known, manufactured concentration of the analytes (drugs and metabolites) within the control material. The studies aim to demonstrate that these known concentrations remain stable over time under specified storage conditions.
8. The sample size for the training set
Not applicable. There is no training set for this type of device.
9. How the ground truth for the training set was established
Not applicable.
§ 862.3280 Clinical toxicology control material.
(a)
Identification. A clinical toxicology control material is a device intended to provide an estimation of the precision of a device test system and to detect and monitor systematic deviations from accuracy resulting from reagent or instrument defects. This generic type of device includes various single, and multi-analyte control materials.(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 the limitations in § 862.9.