(30 days)
Liquichek™ Urine Chemistry Control is intended for use as an assayed quality control urine to monitor the precision of laboratory procedures listed in the package insert.
Liquichek™ Urine Chemistry Control is prepared from human urine with added constituents of human and animal origin, pure chemicals, preservatives and stabilizers. The control is provided in liquid form for convenience.
The provided document is a 510(k) Premarket Notification for a Liquichek™ Urine Chemistry Control device, which is a quality control material. This type of device is used to monitor the precision of laboratory testing procedures for various analytes in urine.
The request asks for information typically associated with clinical studies of diagnostic or screening devices (e.g., sample size, expert ground truth, MRMC studies, standalone performance). However, since the Liquichek™ Urine Chemistry Control is a quality control material and not a diagnostic or screening device itself, the traditional metrics and study types for determining diagnostic performance (like sensitivity, specificity, or reader improvement with AI assistance) are not applicable.
Instead, the "acceptance criteria" for a quality control material typically relate to its stability, accuracy of assigned values, and its ability to consistently perform within expected ranges over its shelf life and open-vial period. The "study that proves the device meets the acceptance criteria" would therefore be stability studies and verification of manufacturing quality.
Based on the provided text, here's a breakdown of the requested information, adapted for a quality control device:
1. A table of acceptance criteria and the reported device performance
For a quality control material, acceptance criteria are generally related to its stability and the accurate assignment of analyte values. The document focuses on stability.
| Acceptance Criteria Category | Specific Criteria (Implicit/Stated) | Reported Device Performance |
|---|---|---|
| Open Vial Stability | All analytes stable within acceptable limits after opening. | 30 days when stored tightly capped at 2-8°C. |
| Shelf Life | All analytes stable within acceptable limits until expiration date. | One year and six months when stored at 2-8°C. |
| Analyte Content | Contains specified analytes as defined in the product specification. | Includes Cortisol in addition to other analytes (Table 1). |
| Matrix | Human urine based. | Human urine based. |
| Form | Liquid. | Liquid. |
| Storage (Unopened) | 2 to 8°C. | 2 to 8°C. |
2. Sample sized used for the test set and the data provenance (e.g. country of origin of the data, retrospective or prospective)
The document states: "Stability studies have been performed..." and "Real time studies will be ongoing to support the shelf life of this product."
- Sample Size (Test Set): The document does not specify the sample size (e.g., number of vials, batches) used for the stability studies.
- Data Provenance: The studies were conducted by Bio-Rad Laboratories, located in Irvine, California, USA. The studies supporting initial claims are likely prospective (real-time stability), with "ongoing" real-time studies for shelf life.
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)
For a quality control material, "ground truth" refers to the assigned values for each analyte. This is typically established through a rigorous process of testing using reference methods and/or multiple calibrated instruments in an accredited laboratory, often involving a consensus of results. The document does not specify the number or qualifications of experts involved in establishing these assigned values. This process is generally part of the manufacturer's quality system and product development, rather than a clinical expert panel.
4. Adjudication method (e.g. 2+1, 3+1, none) for the test set
Not applicable. Adjudication methods like 2+1 are used in clinical studies for interpretation of images or clinical events, often when ground truth is subjective or requires expert consensus. For a quality control material, the "ground truth" (assigned values) are determined analytically and through statistical analysis of multiple measurements, not through expert adjudication in this sense.
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 designed for diagnostic or screening devices where human readers interpret patient data (e.g., medical images). This device is a quality control material, not a diagnostic tool for patient cases, and does not involve human "readers" in the context of diagnostic interpretation.
6. If a standalone (i.e. algorithm only without human-in-the-loop performance) was done
Not applicable. This is a physical reagent, not an algorithm.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc)
For a quality control material, the "ground truth" is typically the assigned value for each analyte. These values are established by the manufacturer through a comprehensive assay process (using highly calibrated instruments and reference methods) and statistical determination, often referred to as "value assignment." It is not based on expert consensus for clinical diagnosis, pathology, or outcomes data, but rather on analytical accuracy and precision.
8. The sample size for the training set
Not applicable. This device does not use machine learning or algorithms that require a "training set." The performance is based on the inherent chemical and physical stability of the material, verified through laboratory studies.
9. How the ground truth for the training set was established
Not applicable. As there is no training set for an algorithm, there is no "ground truth for the training set" to establish in this context.
§ 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.