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Mean 25(OH)D concentration values calculated in respective time periods during 30 years of operation of single diagnostic unit.
| Time period (years) | n | Mean age (months) | 25(OH)D (SD); ng/ml |
|---|---|---|---|
| 1981–99 | 305 | 7 | 51.8 (38.8) |
| 2000–01 | 212 | 7 | 42.9 (27.4) |
| 2002–03 | 152 | 7 | 48.8 (31.7) |
| 2004–05 | 325 | 8 | 34.8 (19.1) |
| 2006 | 334 | 8 | 36.5 (20.0) |
| 2007 | 485 | 8 | 37.2 (23.1) |
| 2008 | 457 | 8 | 32.9 (18.8) |
| 2009 | 481 | 8 | 36.7 (21.7) |
| 2010–11 | 412 | 8 | 29.0 (13.6) |
