Table 2.
Checklist reference interval (RI) approach for creatinine
| Analyte | Creatinine (plasma and serum) |
|---|---|
| Population RI | Based on healthy subjects not hospital patients. |
| eGFR used for decision making. | |
| Units | µmol/L |
| JCTLM-listed traceability or preferred method and reference material | ID-GC/MS and |
| ID-LC/MS (some methods require instrument factors). | |
| SRM 914 (pure creatinine). | |
| SRM 909, 967 (human serum). | |
| Pre-analytics 1. Serum/plasma 2. Sample collection 3. Interferences |
1. Interchangeable. 2. Increases with meat consumption. |
| Analytical differences | Analytically there are no differences. |
| Partitioning by 1. Gender 2. Age |
1. Gender differences. 2. Age-related increases above 60 years not agreed by Renal Physicians. |
| Reporting Interval | 1 µmol/L |