(70 days)
For in vitro diagnostic use in the quantitative determination of glucose in human serum, plasma, urine and CSF on the ADVIA Chemistry systems. Such measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders including diabetes mellitus, neonatal hypoglycemia, idiopathic hypoglycemia, and insulin overdose.
The ADVIA Chemistry Glucose Hexokinase 3 (GLUH 3) method uses a two-component reagent. Sample is added to Reagent 1, which contains the buffer, ATP, and NAD. Absorbance readings of the sample in Reagent 1 are taken and are used to correct for interfering substances in the sample. Reagent 2 is added, which initiates the conversion of glucose and the development of absorbance at 340/410 nm. The difference between the absorbance in Reagent 1 and Reagent 2 is proportional to the glucose concentration.
1. Acceptance Criteria and Device Performance
| Acceptance Criteria (Predicate Device K101854 - using serum, Li-Heparin plasma, K-EDTA plasma) | Reported Device Performance (New Device - K120681, specifically for Na-Fluoride/K-Oxalate plasma) |
|---|---|
| Regression Equation: Y = 1.001x + 0.3 (Serum), Y = 1.001x + 0.2 (Li-Heparin), Y = 1.002x - 0.0 (K-EDTA) | Regression Equation: Y = 1.011x + 0.8 (Na-Fluoride/K-Oxalate plasma) |
| Correlation Coefficient (r): 1.000 (Serum, Li-Heparin, K-EDTA) | Correlation Coefficient (r) for Na-Fluoride/K-Oxalate plasma: 0.999 |
| (Implicitly similar slopes and intercepts to show substantial equivalence for existing plasma types) | Slope 95% CI: 1.003 to 1.019 (contains 1, suggesting good linearity) |
| Intercept 95% CI: -1.18 to 2.73 (contains 0, suggesting minimal bias) | |
| Sample Range: 2-601 mg/dL (covering clinically relevant range) |
The acceptance criteria for the new device (specifically for the Na-Fluoride/K-Oxalate plasma type) are implicitly based on demonstrating substantial equivalence to the predicate device's performance with other plasma types. The reported performance for the new plasma type shows a strong correlation (r=0.999) and a regression equation very close to ideal (slope near 1, intercept near 0), indicating good agreement with the serum measurements using the existing GLUH_3 assay.
2. Sample Size and Data Provenance for Test Set
- Sample Size for Test Set: 82 data-points were included in the calculations. This was derived from 56 matched serum and plasma (Sodium Fluoride/Potassium Oxalate) samples, with some samples being spiked and/or diluted to achieve a wider range of concentrations.
- Data Provenance: Not explicitly stated, but based on the context of a 510(k) submission by Siemens Healthcare Diagnostics Inc., the data is likely from internal studies conducted in a controlled laboratory environment. It is a prospective study as it involves new testing for the expanded sample type.
3. Number of Experts and Qualifications for Ground Truth (Test Set)
- Number of Experts: Not applicable. This study is a method comparison for an in vitro diagnostic device, not an interpretation of images or clinical cases by experts.
- Qualifications of Experts: N/A
4. Adjudication Method (Test Set)
- Adjudication Method: Not applicable. Ground truth for this type of device comparison is established by reference measurement methods or the predicate device's results, not through expert adjudication of subjective interpretations.
5. Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study
- MRMC Study: No, a Multi-Reader Multi-Case (MRMC) comparative effectiveness study was not done. This type of study is typically performed for image-based diagnostic devices where human interpretation plays a significant role.
- Effect Size of AI Improvement: N/A
6. Standalone Performance Study
- Standalone Performance: Yes, a standalone performance study was done for the algorithm (the ADVIA Chemistry GLUH_3 assay) using the new Na-Fluoride/K-Oxalate plasma type. The study compared the results obtained with this new plasma type against results obtained from serum samples using the predicate device's established method. The reported regression equation and correlation coefficient demonstrate the standalone performance of the device with the new sample type.
7. Type of Ground Truth Used
- Type of Ground Truth: The ground truth for the comparison study was established by the results obtained from serum samples using the predicate ADVIA Chemistry GLUH_3 assay (K101854). This is a common approach for method comparison studies for IVD devices, treating the established method (here, using serum) as the reference or "ground truth" to determine the performance of the new application (using Na-Fluoride/K-Oxalate plasma).
8. Sample Size for Training Set
- Sample Size for Training Set: Not explicitly mentioned as a separate "training set" in the context of this 510(k) summary. For in vitro diagnostic assays, the development and initial validation (which might be analogous to "training") typically involve numerous experiments and data points to optimize the reagent formulation and assay parameters. The submitted data focuses on the verification and validation of the new sample type's performance against the established method.
9. How Ground Truth for Training Set was Established
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How Ground Truth for Training Set was Established: As noted above, a distinct "training set" with established ground truth is not typically described in this manner for IVD assay submissions. The development of the ADVIA Chemistry GLUH_3 reagen itself (prior to this modification) would have involved extensive analytical studies, including:
- Using certified reference materials.
- Comparing results to established reference methods (e.g., isotope dilution mass spectrometry, enzymatic reference methods).
- Correlation with clinically validated predicate devices.
For this particular modification, the existing, cleared GLUH_3 reagent used with serum (and other plasma types) serves as the reference, and the new plasma type's performance is evaluated against this established performance.
§ 862.1345 Glucose test system.
(a)
Identification. A glucose test system is a device intended to measure glucose quantitatively in blood and other body fluids. Glucose measurements are used in the diagnosis and treatment of carbohydrate metabolism disorders including diabetes mellitus, neonatal hypoglycemia, and idiopathic hypoglycemia, and of pancreatic islet cell carcinoma.(b)
Classification. Class II (special controls). The device, when it is solely intended for use as a drink to test glucose tolerance, is exempt from the premarket notification procedures in subpart E of part 807 of this chapter subject to the limitations in § 862.9.