(23 days)
The safety and effectiveness of Sigma Diagnostics Electrolyte Reference Reagent, Procedure Number E3891, are demonstrated by its substantial equivalency to Beckman Electrolyte Reference Reagent Kit, Part No. 443315. Both electrolyte reference reagents are used to measure sodium, chloride, potassium, and carbon dioxide concentrations in serum or plasma, sodium, potassium, and chloride concentrations in urine, and chloride concentrations in CSF on the SYNCHRON CX®3 System, and the reaction principles for both reagents are identical.
The Sigma Diagnostics methods use ion selective electrodes for determining sodium, potassium, and chloride and rate of pH change for determining carbon dioxide on the SYNCHRON CX®3 System.
The provided text describes the performance of the Sigma Diagnostics Electrolyte Reference Reagent (Procedure Number E3891) in comparison to the Beckman Electrolyte Reference Reagent Kit (Part No. 443315) on the SYNCHRON CX®3 System. The study aims to demonstrate substantial equivalence.
Here's an analysis based on your requested information:
1. Table of Acceptance Criteria and Reported Device Performance:
The document doesn't explicitly state "acceptance criteria" as defined thresholds for correlation coefficients or regression equations. Instead, it presents the achieved performance metrics as evidence of substantial equivalence to the predicate device. The implied acceptance is that the correlation and regression fall within an acceptable range for a substantially equivalent device. Similarly, for precision, the stated %CVs are the achieved performance, implying these are considered acceptable.
| Metric (Analyte, Sample Type) | Reported Sigma Diagnostics Performance | Implied Acceptance Criteria (relative to predicate) |
|---|---|---|
| Correlation Coefficient | ||
| Sodium (Serum) | 0.963 | High correlation (implied >~0.95 given the values) |
| Potassium (Serum) | 0.999 | High correlation |
| Chloride (Serum) | 0.973 | High correlation |
| Total CO2 (Serum) | 0.992 | High correlation |
| Sodium (Urine) | 0.997 | High correlation |
| Potassium (Urine) | 0.998 | High correlation |
| Chloride (Urine) | 0.997 | High correlation |
| Chloride (CSF) | 0.891 | High correlation (lower but still presented as acceptable) |
| Regression Equation (y = Sigma, x = Beckman) | ||
| Sodium (Serum) | y = 0.90x + 13.48 | Slope close to 1, intercept close to 0 (indicating good agreement) |
| Potassium (Serum) | y = 0.98x + 0.08 | Slope close to 1, intercept close to 0 |
| Chloride (Serum) | y = 0.91x + 10.52 | Slope close to 1, intercept close to 0 |
| Total CO2 (Serum) | y = 0.95x + 1.54 | Slope close to 1, intercept close to 0 |
| Sodium (Urine) | y = 0.95x - 0.10 | Slope close to 1, intercept close to 0 |
| Potassium (Urine) | y = 0.97x + 0.49 | Slope close to 1, intercept close to 0 |
| Chloride (Urine) | y = 0.97x + 2.06 | Slope close to 1, intercept close to 0 |
| Chloride (CSF) | y = 0.98x + 4.00 | Slope close to 1, intercept close to 0 |
| Precision (%CV) | ||
| Sodium (Serum) |
§ 862.1665 Sodium test system.
(a)
Identification. A sodium test system is a device intended to measure sodium in serum, plasma, and urine. Measurements obtained by this device are used in the diagnosis and treatment of aldosteronism (excessive secretion of the hormone aldosterone), diabetes insipidus (chronic excretion of large amounts of dilute urine, accompanied by extreme thirst), adrenal hypertension, Addison's disease (caused by destruction of the adrenal glands), dehydration, inappropriate antidiuretic hormone secretion, or other diseases involving electrolyte imbalance.(b)
Classification. Class II.