(178 days)
The intended use for the N-ASSAY Glu-UL Reagent is for the quantitative determination of glucose in serum, plasma, urine, and cerebrospinal fluid in the diagnosis and treatment of diabetes mellitus, neonatal hypoglycemia and idiopathic hypoglycemia, and of pancreatic islet cell carcinoma. For in vitro diagnostic use only.
The N-ASSAY Glu-UL reagent is based on an enzymatic hexokinase/glucose-6phosphate dehydrogenase method, shows good correlation with similar glucose reagents, practically no interference by coexistent substances, high sensitivity with good reproducibility, wide assay range, and is a convenient ready-to-use liquid type reagent.
In this method, serum D-glucose is phosphorylated by hexokinase (HK) in the presence of adenosine triphosphate (ATP) to produce glucose-6-phosphate (G-6-P) and adenosine diphosphate (ADP). Glucose-6-phosphate dehydrogenase (G-6-PDH) specifically oxidizes G-6-P to 6-Phosphogluconate with the concurrent reduction of nicotinamide adenine dinucleotide phosphate (NADP) to nicotinamide adenine dinucleotide phosphate reduced (NADPH). The NADPH produced absorbs light at 340 nm (main) and 405 nm (sub) and can be detected spectrophotometrically. The increase in absorbance measured at 340 nm (main) and 405 (sub), due to the formation of the NADPH, is directly proportional to the glucose concentration in the sample.
The provided text describes a 510(k) submission for the N-ASSAY Glu-UL (Glucose Assay Reagent). It details the device's function and provides comparison studies against predicate devices to demonstrate substantial equivalence.
Here's an analysis of the acceptance criteria and study information:
1. Table of Acceptance Criteria and Reported Device Performance
The submission does not explicitly state pre-defined acceptance criteria in terms of specific thresholds for correlation coefficients or regression equations. Instead, it demonstrates "substantial equivalence" to predicate devices, implying that the performance must be comparable to these already marketed devices.
| Acceptance Criteria (Implied by Substantial Equivalence to Predicate) | Reported Device Performance | Comments |
|---|---|---|
| Serum Samples: Performance comparable to Medical Analysis Systems Glucose liquid reagent (K853464) | Correlation coefficient: 0.99587 | High correlation indicates strong agreement. |
| Regression equation: y = 0.8861x + 4.7012 | The slope and intercept suggest a slight difference in absolute values compared to the predicate, but with a strong linear relationship. | |
| Precision acceptable on a day-to-day basis | Precision studies indicate acceptable values | No specific metrics for "acceptable" are provided. |
| Minimum detectable level comparable to predicate | Minimum detectable level: 1 mg/dl | No direct comparison to the predicate's MDL is given, but 1 mg/dl is stated. |
| Linearity comparable to predicate | Linear to 1,000 mg/dl | No direct comparison to the predicate's linearity range is given, but 1,000 mg/dl is stated. |
| Urine Samples: Performance comparable to Boehringer Mannheim Glucose assay (K812303) | Correlation coefficient: 0.9989 | High correlation indicates strong agreement. |
| Regression equation: y = 1.038x + 1.528 | The slope close to 1 and small intercept suggest good agreement with the predicate. | |
| Limit of quantitation comparable to predicate | Limit of quantitation: 0.3 mg/dl | No direct comparison to the predicate's LOQ is given, but 0.3 mg/dl is stated. |
| CSF Samples: Performance comparable to Boehringer Mannheim Glucose assay (K812303) | Correlation coefficient: 0.9923 | High correlation indicates strong agreement. |
| Regression equation: y = 1.080x + -1.233 | The slope close to 1 and small intercept suggest good agreement with the predicate. | |
| Limit of quantitation comparable to predicate | Limit of quantitation: 0.3 mg/dl | No direct comparison to the predicate's LOQ is given, but 0.3 mg/dl is stated. |
2. Sample Size Used for the Test Set and Data Provenance
The document does not explicitly state the sample sizes used for the comparison studies for serum, urine, or CSF samples. It only mentions "serum samples," "urine samples," and "CSF samples" in a general sense.
The data provenance is not explicitly mentioned (e.g., country of origin, retrospective or prospective). However, given the context of a 510(k) submission for a diagnostic reagent, it is highly likely these were prospective laboratory studies.
3. Number of Experts Used to Establish the Ground Truth for the Test Set and Qualifications of Those Experts
This information is not applicable in this context. The "ground truth" for a quantitative diagnostic reagent like N-ASSAY Glu-UL is typically established by:
- Reference Methods: Highly accurate and precise laboratory methods.
- Predicate Device Results: The results obtained from the legally marketed predicate devices are used as the comparative "truth" to assess the performance of the new device.
There were no human experts evaluating images or making diagnoses against which the device's output would be compared.
4. Adjudication Method for the Test Set
This information is not applicable. Since the "ground truth" is established by reference methods or predicate device results, there is no need for expert adjudication. The comparison is made directly between the quantitative results of the new device and the predicate device.
5. If a Multi-Reader Multi-Case (MRMC) Comparative Effectiveness Study was done, If so, what was the effect size of how much human readers improve with AI vs without AI assistance
This information is not applicable. An MRMC study is relevant for diagnostic imaging devices where human readers interpret images, often with and without AI assistance. The N-ASSAY Glu-UL is a chemical reagent for quantitative blood and fluid analysis, not an imaging device.
6. If a Standalone (i.e. algorithm only without human-in-the-loop performance) was done
The studies described are inherently "standalone" in the sense that they evaluate the performance of the reagent itself (which is analogous to an "algorithm" in a chemical assay) against predicate methods. There is no "human-in-the-loop" aspect being evaluated in these comparison studies; the studies assess how well the reagent performs in generating quantitative results.
7. The type of ground truth used (expert consensus, pathology, outcomes data, etc.)
The ground truth used for the comparison studies was the results obtained from the predicate devices:
- For serum samples: Medical Analysis Systems Glucose liquid reagent (K853464)
- For urine and CSF samples: Boehringer Mannheim Glucose assay (K812303)
These predicate devices are themselves established glucose measurement methods.
8. The sample size for the training set
The document does not provide information on a "training set" for the N-ASSAY Glu-UL reagent. This is because the device is a chemical reagent, not a machine learning or AI-based system that typically requires a training set. The performance is based on the chemical reactions and optical detection, which are inherent properties of the reagent's formulation.
9. How the ground truth for the training set was established
As there is no mention of a "training set" for this chemical reagent, this information is not applicable. The ground truth for evaluating the reagent's performance (as described in point 7) was established by comparing its results to established predicate methods.
§ 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.