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The QMS® Amikacin assay is intended for the quantitative determination of amikacin in human serum or plasma on automated clinical chemistry analyzers.

The results obtained are used in the diagnosis and treatment of amikacin overdose and in monitoring levels of amikacin to ensure appropriate therapy.

The QMS® Amikacin assay system is a homogeneous assay utilizing particle agglutination technology and is based on the competitive binding principle.

In particle agglutination assays, the degree of agglutination is inversely proportional to the quantity of free drug in the reaction well. Hence, if no drug is present in the sample, the antibodies in the QMS Amikacin Antibody Reagent (R1) will bind only to the bound drug on the particle which will cause it to agglutinate and will result in higher absorbance. If increased amount of competing drug is present in the sample, this will result in decreased binding of bound drug by the antibody, resulting in a relative decrease in particle agglutination. This in turn results in lower absorbance.

The precise relationship between particle agglutination of the unlabeled drug in the sample is established by measuring the absorbance values of calibrators with known concentration of the drug. The absorbance of unknown samples can be interpolated from the absorbance values of the calibration curve and the concentration of the drug present in the sample can be calculated.

The assay consists of reagents R1: anti-amikacin monoclonal antibody and R2: amikacin-coated microparticles. A six-level set of QMS® Amikacin Calibrators (A through F) is used to calibroothe assay.

Here's a breakdown of the acceptance criteria and study information for the QMS® Amikacin assay, based on the provided document:

1. Table of Acceptance Criteria and Reported Device Performance

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

• Accuracy: Samples were spiked human serum. No specific number for "samples analyzed" is given, but it mentions "in duplicate." The specific source/country of the human serum is not mentioned. This appears to be a laboratory-controlled, prospective study.
• Linearity: Not explicitly stated, but based on "a study based on the NCCLS guideline EP6." A set of 5 theoretical concentrations was tested, each in duplicate. USP Amikacin was used, indicating an in vitro, laboratory-controlled prospective study.
• Sensitivity: Not explicitly stated, but related to the lowest detectable dose from laboratory measurements.
• Method Comparison: N = 56 patient samples. The data provenance (country of origin, retrospective/prospective) is not explicitly stated, but the mention of "patient samples" suggests retrospective or prospective clinical samples. It does not state if these were collected specifically for this study or were archived.
• Precision: 80 measurements for each of the three control levels over multiple runs/days. This refers to laboratory-controlled measurements of quality control materials.
• Interferences:
  • Endogenous Substances: N=2 or N=3 for each interferent tested. These were likely laboratory-prepared samples with added interferents, a prospective study.
  • Human Anti-Mouse Antibodies (HAMA): Not explicitly stated, but given as "Rep 1" and "Rep 2" for HAMA Type-1 and Type-2, suggesting laboratory-spiked samples.
  • Cross-reactants: No 'N' is listed, but various cross-reactant drugs were tested at specified concentrations. This would be a laboratory-controlled study.
  • Anticoagulants: Not explicitly stated, but likely laboratory-controlled comparison of serum and plasma samples, a prospective study.

3. Number of Experts Used to Establish Ground Truth and Qualifications

This document describes the performance characteristics of an in-vitro diagnostic (IVD) device for measuring a drug concentration. The "ground truth" in this context is established by:

• Known Reference Values: For accuracy, linearity, and sensitivity, the ground truth is the spectroscopically pure USP traceable amikacin spiked into human serum at known concentrations.
• Reference Method: For method comparison, the ground truth is considered the results obtained from the predicate device, the Abbott TDx/TDxFLx® Amikacin assay.

Therefore, there were no clinical experts (e.g., radiologists) involved in establishing the "ground truth" in the way one would for image interpretation or diagnosis. The ground truth relies on analytical chemistry principles and a comparative reference method for this type of device.

4. Adjudication Method for the Test Set

Not applicable. This is an analytical device for quantitative measurement, not a human-interpreted diagnostic output requiring adjudication. The performance is assessed by comparing the device's output to known input concentrations or to measurements from a predicate device.

5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study

Not applicable. This is a standalone analytical device, not a human-in-the-loop system where human reader performance is being evaluated or augmented by AI.

6. Standalone (Algorithm Only) Performance

Yes, the studies presented here are entirely standalone performance evaluations of the QMS® Amikacin assay. The device measures amikacin concentration in a sample without human interpretation or intervention in the measurement process itself. The "algorithm" here refers to the underlying chemical reaction and optical detection described in the "Description of Device," which is inherent to the device's operation.

7. Type of Ground Truth Used

• Known (Spiked) Concentrations: For accuracy, linearity, and sensitivity, the ground truth was established by precisely preparing samples with known concentrations of USP traceable amikacin.
• Reference Standard (Predicate Device): For method comparison, the Abbott TDx/TDxFLx® Amikacin assay served as the reference standard to which the new device's results were compared.

8. Sample Size for the Training Set

No information about a "training set" is provided. This is a traditional IVD device, not a machine learning or AI-driven system that would typically have a distinct "training set" and "test set" in the computational sense. The "development" and "validation" of the assay are implied by the studies conducted, but not in the context of training a machine learning model.

9. How Ground Truth for the Training Set Was Established

Not applicable, as no dedicated "training set" is described for this type of device.

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