TABLE 2.
Deciles of serum 25(OH)D concentrations from the NANS of adults aged 18–84 y in Ireland, 2008–2010, as measured by using the IDS ELISA, VDSP-protocol–projected estimates, and LC–tandem MS1
| Serum 25(OH)D |
|||
| Deciles of serum 25(OH)D | Via IDS ELISA | VDSP-protocol predicted (95% CI) | Via LC–tandem MS2 |
| nmol/L | |||
| 10 | 32.4 | 28.0 (26.6, 29.8) | 27.8 |
| 20 | 38.7 | 35.6 (34.1, 37.7) | 34.9 |
| 30 | 43.5 | 41.5 (40.1, 43.1) | 40.4 |
| 40 | 50.1 | 47.6 (46.0, 48.7) | 46.3 |
| 50 | 57.1 | 52.5 (51.1, 53.4) | 53.4 |
| 60 | 63.2 | 56.8 (55.3, 58.2) | 58.9 |
| 70 | 70.5 | 61.9 (60.3, 63.5) | 65.9 |
| 80 | 79.9 | 68.4 (66.4, 70.1) | 74.1 |
| 90 | 91.8 | 76.8 (75.4, 78.6) | 86.3 |
1
IDS, Immuno Diagnostic Systems Ltd; LC–tandem MS, liquid chromatography–tandem mass spectrometry; NANS, Irish National Adult Nutrition Survey; VDSP, Vitamin D Standardization Program; 25(OH)D, 25-hydroxyvitamin D.
2
Measured by using LC–tandem MS, which was traceable and standardized to the reference measurement procedure at Ghent University.