(29 days)
The Magnesium assay is used for the quantitation of magnesium in human serum, plasma, or urine. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low serum levels of magnesium) and hypermagnesemia (abnormally high serum levels of magnesium).
Magnesium is an in vitro diagnostic assay for the quantitative determination of magnesium in human serum, plasma, or urine. The Magnesium assay is a clinical chemistry assay which utilizes an arsenazo dye which binds preferentially with magnesium. The absorbance of the arsenazo magnesium complex is measured at 550 nm and is proportional to the concentration of magnesium present in the sample.
Here's an analysis of the provided 510(k) summary, aiming to extract the requested information about acceptance criteria and the supporting study:
The provided document describes a 510(k) submission for a diagnostic assay, not a device that involves image analysis or human interpretation. Therefore, many of the requested fields related to human readers, experts, ground truth adjudication, and image data provenance are not applicable. I will fill in what is relevant to an in vitro diagnostic (IVD) assay.
Device: Abbott Laboratories Magnesium Assay
This is an in vitro diagnostic assay for the quantitative determination of magnesium in human serum, plasma, or urine, utilizing an arsenazo dye.
1. Table of Acceptance Criteria and Reported Device Performance
The acceptance criteria for this diagnostic assay are based on demonstrating "substantial equivalence" to predicate devices. For IVD assays, this typically means that the new device's performance characteristics (e.g., correlation, precision, linearity, sensitivity) are comparable to or within acceptable limits of the legally marketed predicate device(s). The specific numerical acceptance criteria themselves are not explicitly stated in the summary (e.g., "correlation coefficient must be ≥ 0.95"). Instead, the results are presented and deemed "acceptable" or demonstrating "substantial equivalence."
| Performance Characteristic | Acceptance Criteria (Implicit) | Reported Device Performance |
|---|---|---|
| Correlation (Serum) | Substantial equivalence to Roche Cobas Mira Plus Magnesium assay (implied acceptable coefficient, slope, and intercept for clinical utility). | Correlation coefficient = 0.9707 |
| Slope = 1.067 | ||
| Y-intercept = 0.147 mEq/L | ||
| Correlation (Urine) | Substantial equivalence to Boehringer Mannheim Magnesium assay (implied acceptable coefficient, slope, and intercept for clinical utility). | Correlation coefficient = 0.9835 |
| Slope = 0.933 | ||
| Y-intercept = 0.133 mEq/L | ||
| Precision (Serum) | Substantial equivalence in within-run, between-run, and between-day variability compared to predicate (implied acceptable %CV for clinical utility). | Total %CV Level 1 = 5.9% |
| Total %CV Level 2 = 3.7% | ||
| Precision (Urine) | Substantial equivalence in within-run, between-run, and between-day variability compared to predicate (implied acceptable %CV for clinical utility). | Total %CV Level 1 = 5.9% |
| Total %CV Level 2 = 4.4% | ||
| Linearity | Demonstrate linearity across the intended measurement range. | Linear up to 6 mEq/L |
| Limit of Quantitation | Demonstrate adequate sensitivity for clinical utility. | 0.4 mEq/L |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the numerical sample size (number of patient samples) for the "comparative performance studies" (test set). It mentions "two levels of control material" for precision studies.
- Sample Size for Test Set: Not explicitly stated (number of patient samples for method comparison). It mentions "two levels of control material" for precision.
- Data Provenance: Not specified (e.g., country of origin). The studies appear to be retrospective in the sense that they are comparing the new assay's results on samples to those run on established predicate devices, which often involves using existing or collected samples in a laboratory setting. Details on patient demographics or collection methods are not provided.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications
- Not applicable. This is an in vitro diagnostic assay that produces a quantitative numerical result. "Ground truth" is established by the performance of the predicate devices or by reference methods, not by expert interpretation.
4. Adjudication Method for the Test Set
- Not applicable. The "ground truth" for method comparison and precision in IVD assays is based on the results from the predicate device and the inherent variability of the assay itself, respectively. There's no human adjudication process involved for this type of test.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- No. This is an in vitro diagnostic assay. Such studies are designed for devices where human interpretation of images or other subjective data is involved. The device produces a quantitative measurement.
6. Standalone Performance Study
Yes, a standalone performance study was conducted in the sense that the performance characteristics of the new Magnesium assay (precision, linearity, limit of quantitation) were evaluated independently. However, the primary evidence for substantial equivalence relies on comparative performance with predicate devices for accuracy.
- Standalone Performance Evaluated: Precision (within-run, between-run, between-day), linearity, and limit of quantitation (sensitivity).
- Results:
- Precision (Serum): Total %CV Level 1 = 5.9%, Level 2 = 3.7%
- Precision (Urine): Total %CV Level 1 = 5.9%, Level 2 = 4.4%
- Linearity: Up to 6 mEq/L
- Limit of Quantitation: 0.4 mEq/L
7. Type of Ground Truth Used
For the method comparison (accuracy) component, the results obtained from the predicate devices were used as the reference ("ground truth") for comparison.
- Predicate Devices:
For other performance characteristics like precision, the "ground truth" is typically an expected value of the control material or simply the direct measurement of statistical variability.
8. Sample Size for the Training Set
The document does not refer to a "training set" in the context of machine learning or AI. This assay is a chemical measurement method, not an algorithm that learns from data.
9. How the Ground Truth for the Training Set was Established
- Not applicable. As above, there is no "training set" for this type of in vitro diagnostic assay.
§ 862.1495 Magnesium test system.
(a)
Identification. A magnesium test system is a device intended to measure magnesium levels in serum and plasma. Magnesium measurements are used in the diagnosis and treatment of hypomagnesemia (abnormally low plasma levels of magnesium) and hypermagnesemia (abnormally high plasma levels of magnesium).(b)
Classification. Class I.