Table II.
Laboratory work-up in SEPHAR II
| Test | Methodology/reagents/manufacturer | Analyzer | Analytical characteristics of the method applied | |||||
|---|---|---|---|---|---|---|---|---|
| Bias | Within-run imprecision | Between-run imprecision | ||||||
| N | P | N | P | N | P | |||
| Serum creatinine | Jaffe method/picric acid in alkaline milieu/Roche | Cobas 6000 | –1.82 | –6.09 | 1.08 | 1.49 | 2.3 | 1.61 |
| eGFR | Calculated using the simplified MDRD equation: eGFR = 175 × [(S × 0.0113)–1.154] × [age (years)]–0.203 × Z; where: S – serum creatinine [µmol/l]; Z = 0.742 (for females) and 1 (for males) | |||||||
| Serum uric acid | Enzymatic/uricase, peroxidase/Roche | Cobas 6000 | 0 | –2 | 0.9 | 0.7 | 2.2 | 2.2 |
| Serum potassium | ISE/indirect ion-selective electrode/Roche | Cobas 6000 | 0.7 | 0.7 | 0.5 | 0.5 | 0.75 | 0.92 |
| Serum triglycerides | Enzymatic/glycerol kinase and glycerol phosphatase/Roche | Cobas 6000 | –4.17 | –3.81 | 1.12 | 0.69 | 2.1 | 2.3 |
| Serum total cholesterol | Enzymatic/cholesterol esterase and cholesterol oxidase/Roche | Cobas 6000 | –0.36 | 0.36 | 0.65 | 1.18 | 1.79 | 1.84 |
| Serum HDL-cholesterol | Enzymatic/peg-cholesterol oxidase/Roche | Cobas 6000 | –3.11 | –4.14 | 1.23 | 0.9 | 2.05 | 3.16 |
| Serum LDL-cholesterol | Using Friedewald formula: LDL-C [mg/dl] = total cholesterol [mg/dl] – HDL-C [mg/dl] – triglycerides [mg/dl]/5. If triglyceride concentration > 350 mg/dl, Friedewald formula cannot be used | |||||||
| Plasma glucose | Enzymatica/hexokinase and glucose-6-phosphate dehydrogenase/Roche | Cobas 6000 | –0.68 | –2.89 | 1.16 | 0.99 | 1.68 | 1.5 |
| Glycated hemoglobin (HbA1c) | Tinia, IFCC standardised and DCC/NGSP traceable/Roche | Cobas 6000 | –3.74 | –8.14 | 1.5 | 1.1 | 1.34 | 2.06 |
| Albuminuria | Immunoturbidimetry/Roche | Cobas 6000 | 0.93 | –2.3 | 2.5 | 2.19 | 2.5 | 1.1 |