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For in vitro diagnostic use only

The GLU test within the VITROS XT Chemistry Products GLU-Ca Slides quantitatively measures glucose (GLU) concentration in serum, plasma, urine, and cerebrospinal fluid using VITROS XT 7600 Integrated Systems. Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders mellitus. neonatal hypoglycemia, and idiopathic hypoglycemia, and of pancreatic islet cell carcinoma.

The Ca test within the VITROS XT Chemistry Products GLU-Ca Slides quantitatively measures calcium (Ca) concentration in serum, plasma, and urine using VITROS XT 7600 Integrated Systems. Calcium measurements are used in the diagnosis and treatment of parathyroid disease, a variety of bone diseases, chronic renal disease and tetany (intermittent muscular contractions or spasms).

Special conditions for use statement: For prescription use only.

The new device, the VITROS XT Chemistry Products GLU-Ca Slides is a single device that contains both a GLU test and a Ca test side by side separated by a plastic barrier sealed within a single slide frame. In this format, individual reactions occur and test results are generated for each analyte independently of the other analyte.

For glucose measurement, a drop of patient sample is deposited on the GLU test element of the slide and is evenly distributed by the spreading layer to the underlying layers. The oxidation of sample glucose is catalyzed by glucose oxidase to form hydrogen peroxide and gluconate. This reaction is followed by an oxidative coupling catalyzed by peroxidase in the presence of dye precursors to produce a dye. The intensity of the dye is measured by reflected light. The dye system used is closely related to that first reported by Trinder. ' The chemistry of the glucose slides has been described by Curme, et al.

For calcium measurement, a drop of patient sample is deposited on the Ca test element of the slide and is evenly distributed by the spreading layer to the underlying layers. The bound calcium is dissociated from binding proteins, allowing the calcium to penetrate through the spreading layer into the underlying reagent layer. There, the calcium forms a complex with Arsenazo III dye, causing a shift in the absorption maximum. After incubation, the reflection density of the colored complex is measured spectrophotometrically. The amount of colored complex formed is proportional to the calcium concentration in the sample.

The provided document describes the analytical performance of the VITROS XT Chemistry Products GLU-Ca Slides for measuring Glucose (GLU) and Calcium (Ca) concentrations. Here's a breakdown of the requested information:

1. Acceptance Criteria and Reported Device Performance

The acceptance criteria are not explicitly stated as numerical targets in the document. Instead, the study aims to show substantial equivalence to predicate devices and acceptable performance based on established clinical laboratory guidelines (CLSI protocols). The "reported device performance" is summarized from the tables in the document.

Table of Acceptance Criteria (Implied by Study Design) and Reported Device Performance

2. Sample Sizes Used for the Test Set and Data Provenance

• Method Comparison:
  • GLU Serum: N=116
  • GLU Urine: N=103
  • GLU CSF: N=149
  • Ca Serum: N=112
  • Ca Urine: N=119
• Precision:
  • GLU (Serum, Urine, CSF): 80 observations (2 replicates per run, 2 runs per day over 20 days) for each fluid type.
  • Ca (Serum, Urine): 80 observations (2 replicates per run, 2 runs per day over 20 days) for each fluid type.
• Detection Limits (LoQ, LOB, LOD): Not explicitly stated as a number of patient samples, but the determination was based on CLSI EP17-A2.
• Linearity: Not explicitly stated as a number of patient samples, but involved "A series of twenty proportionally related admixtures of low and high test fluids" for each test and sample type, each tested in quadruplicate.
• Specificity (Interference): Not explicitly stated as a number of patient samples. Involves testing of "substances" at specified concentrations in serum, urine, and CSF.

Data Provenance: The document does not specify the country of origin of the data. The studies are non-clinical analytical performance studies, which typically use well-characterized, banked samples or prepared control materials rather than 'retrospective' or 'prospective' patient data in the clinical sense. The samples for method comparison are referred to as "patient samples."

3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts

This document describes the analytical performance of an in vitro diagnostic device. The "ground truth" here refers to the reference method measurements for Method Comparison studies or the known concentrations of control materials for Precision, Detection Limits, Linearity, and Specificity studies.

• No human experts (e.g., radiologists) are involved in establishing ground truth for chemical analyte measurements.
• The ground truth is established by the predicate devices (VITROS Chemistry Products GLU Slides and VITROS Chemistry Products Ca Slides on the VITROS 5600 Integrated System) for method comparison studies, and by the known values of patient pools and quality control materials for precision, detection limits, and linearity. For specificity, the ground truth is the known concentration of the interferent and the analyte in the prepared samples.

4. Adjudication Method for the Test Set

Not applicable. This is an analytical performance study for an in vitro diagnostic device, not a study involving human interpretation or adjudication of diagnostic findings.

5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study Was Done

No. This is an analytical performance study for an in vitro diagnostic device, not an MRMC study comparing human reader performance.

6. If a Standalone (i.e., algorithm only without human-in-the-loop performance) Was Done

Yes, this entire document describes studies of the standalone performance of the VITROS XT Chemistry Products GLU-Ca Slides on the VITROS XT 7600 Integrated System. The performance metrics presented (method comparison, precision, linearity, detection limits, specificity) are all measures of the device's analytical capabilities without human intervention in the result generation or interpretation beyond operating the instrument and collecting the samples.

7. The Type of Ground Truth Used

• Method Comparison: Ground truth was established by the predicate devices (VITROS Chemistry Products GLU Slides [K182072] and VITROS Chemistry Products Ca Slides [K072440]) run on the VITROS 5600 Integrated System.
• Precision and Linearity: Ground truth was established by known concentrations of patient pools and quality control materials.
• Detection Limits (LoQ/LOD/LOB): Ground truth was based on the known concentrations of prepared samples and determined using statistical methods compliant with CLSI EP17-A2.
• Specificity (Interference): Ground truth was based on the known concentrations of the target analyte and the potential interfering substances in prepared samples.

8. The Sample Size for the Training Set

Not applicable. This document describes an analytical validation, not a machine learning study that typically involves "training sets." The device is a chemistry analyzer system, not an AI algorithm that learns from data.

9. How the Ground Truth for the Training Set Was Established

Not applicable, as there is no "training set" in the context of this device's validation.

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