(105 days)
The QMS® Lamotrigine assay is intended for the quantitative determination of lamotrigine in human serum or plasma on automated clinical chemistry analyzers.
Lamotrigine concentrations can be used as an aid in management of patients treated with lamotrigine.
The QMS® Lamotrigine Calibrator set is intended for use in calibration of the QMS Lamotrigine assay.
The QMS® Lamotrigine Control set is intended for use in quality control of the QMS Lamotrigine assay.
The QMS Lamotrigine assay system is a homogeneous assay utilizing particle agglutination technology and is based on the competitive binding principle.
The assay consists of reagents R1: anti-Lamotrigine sheep polyclonal antibody and R2: Lamotriginecoated microparticles. A six-level set of QMS Lamotrigine Calibrators (A through F) is used to calibrate the assay. A three-level set of QMS Lamotrigine Controls (1 thro the assay.
The provided document describes the K062966 QMS® Lamotrigine assay, a homogeneous particle-enhanced turbidimetric immunoassay for the quantitative determination of lamotrigine in human serum or plasma.
Here's an analysis of the acceptance criteria and the study that proves the device meets them:
1. Table of Acceptance Criteria and Reported Device Performance
The document does not explicitly present a table of "acceptance criteria" with specific pass/fail thresholds for each performance characteristic. Instead, it describes general methods used for testing and states that performance testing verified the device functions as intended and satisfied design specifications. However, we can infer some criteria and the reported performance from the "SUMMARY OF CLINICAL TESTING" section.
| Performance Characteristic | Acceptance Criteria (Inferred) | Reported Device Performance |
|---|---|---|
| Accuracy and Linearity | Demonstrated linearity and accuracy across the reportable range. | Determined by a study based on NCCLS guideline EP6. |
| Sensitivity (LOQ) | Establish the Limit of Quantitation. | Functional Sensitivity (LOQ) determined to be 2.0 µg/mL. |
| Assay Range | Define the reportable range of the assay. | Reportable range: 2.0 to 40.0 µg/mL. |
| Method Comparison | Show correlation with a comparative method. | Correlation studies conducted using NCCLS Guideline EP9. |
| Precision | Demonstrate acceptable precision. | Performed using NCCLS guideline EP5. |
| Specificity | Minimal or no significant cross-reactivity with metabolites and other drugs. | N-2 oxide shows cross-reactivity but is in very minor concentrations. No significant cross-reactivity with other metabolites. |
| Interferences | Minimal or no significant interference from common drugs. | Of 26 drugs tested, none showed cross-reactivity. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not specify the exact sample sizes for the test sets used in each study (Accuracy and Linearity, Sensitivity, Method Comparison, Precision, Specificity, Interferences).
- Data Provenance: The document does not explicitly state the country of origin or if the data was retrospective or prospective. However, given it's a clinical chemistry assay for human serum/plasma, it's highly likely the samples were human biological specimens.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not provided in the document. For an in vitro diagnostic (IVD) assay like this, "ground truth" is typically established by reference methods or validated techniques, not necessarily by "experts" in the same way it would be for imaging diagnostics requiring interpretation.
4. Adjudication Method (e.g., 2+1, 3+1, none) for the Test Set
This information is not applicable and therefore not provided. Adjudication methods are typically relevant for studies involving human interpretation of results (e.g., in imaging or pathology where multiple readers might disagree). For a quantitative chemical assay, the "truth" is determined by the output of a reference instrument or method.
5. Multi Reader Multi Case (MRMC) Comparative Effectiveness Study
A Multi Reader Multi Case (MRMC) comparative effectiveness study was not performed or described. This type of study is relevant for evaluating the performance of human readers, often aided by AI, in complex diagnostic tasks (e.g., radiology). This device is a quantitative immunoassay, not an AI-assisted diagnostic imaging tool.
6. Standalone (Algorithm Only Without Human-in-the-Loop Performance) Study
This device is a standalone assay kit that performs a quantitative measurement on automated clinical chemistry analyzers. The "algorithm" is the biochemical reaction and measurement process itself, not a separate computational algorithm that assists a human. Therefore, the performance described is the standalone performance of the assay system without human interpretation as a primary component of the diagnostic result. The results (lamotrigine concentrations) are then used by clinicians for patient management.
7. Type of Ground Truth Used
The ground truth for this type of quantitative assay would typically be established by:
- Reference Methods: Highly accurate and precise analytical methods (e.g., Gas Chromatography-Mass Spectrometry (GC-MS) or Liquid Chromatography-Mass Spectrometry (LC-MS)) for determining the true concentration of lamotrigine in samples.
- Spiked Samples: Known concentrations of lamotrigine added to a matrix (e.g., human serum or plasma that is negative for lamotrigine) to assess accuracy and linearity.
- Patient Samples: Used for method comparison against a legally marketed predicate device or a well-established reference method.
The document implicitly refers to these by mentioning "Accuracy and linearity were determined..." and "Correlation studies were conducted using patient samples..." indicating that the "ground truth" for those studies would have been the results from a reference method or the assigned values from spiked samples.
8. Sample Size for the Training Set
The document does not mention a training set because this is a traditional immunoassay, not a machine learning or AI-based device that requires "training." The "training" of such a system involves developing the reagents and optimizing the assay conditions.
9. How the Ground Truth for the Training Set Was Established
As there is no "training set" in the context of machine learning, this question is not applicable. The development of the assay's reagents and protocols is based on extensive biochemical research and optimization studies rather than "ground truth" established for a training dataset.
§ 862.3350 Diphenylhydantoin test system.
(a)
Identification. A diphenylhydantoin test system is a device intended to measure diphenylhydantoin, an antiepileptic drug, in human specimens. Measurements obtained by this device are used in the diagnosis and treatment of diphenylhydantoin overdose and in monitoring levels of diphenylhydantoin to ensure appropriate therapy.(b)
Classification. Class II.