Table 1.
Vitamin D status of the studied subjects based on different systems of 25(OH)D analysis [n (%)] before and after harmonization based on HPLC results
| System | Before harmonization | P valuea | After harmonization | P valuea | ||||
|---|---|---|---|---|---|---|---|---|
| Deficient | Insufficient | Sufficient | Deficient | Insufficient | Sufficient | |||
| HPLC | 97 (35.8) | 81 (29.9) | 93 (34.3) | — | 97 (35.8) | 81 (29.9) | 93 (34.3) | — |
| ECL‐Roche | 87 (32.7) | 77 (28.9) | 104 (38.3) | .016 | 106 (39.8) | 69 (25.9) | 91 (34.2) | .368 |
| CLIA‐Diasorin | 120 (48.4) | 83 (33.5) | 45 (18.1) | <.001 | 76 (30.6) | 89 (35.9) | 83 (33.5) | .172 |
| EIA‐DIAsource | 40 (15.0) | 110 (41.4) | 116 (43.6) | <.001 | 79 (29.7) | 109 (41.0) | 78 (29.3) | .614 |
| RIA‐DIAsource | 68 (30.4) | 59 (26.3) | 97 (43.3) | .760 | 87 (38.8) | 54 (24.1) | 83 (37.1) | .010 |
Vitamin D status definitions based on serum 25(OH)D concentration (nmol/L): deficiency: <27.5; insufficiency: 27.6‐50.0; sufficiency: >50.
a
Comparison of each method with HPLC was done by Wilcoxon's test.