Prospective association of 25(OH)D3, 25(OH)D2, phosphate, calcium and PTH concentrations (assessed at mean age of 9.8 years with key stage 3 scores (assessed at age 13–14 years) (n=3171)
| Exposure | Outcome | SD change in outcome per doubling of exposure (95% CI) | ||
| Model 1 | Model 2 | Model 3 | ||
| 25(OH)D3 | English total score | 0.01 (−0.01 to 0.03) | 0.01 (−0.01 to 0.03) | 0.00 (−0.02 to 0.02) |
| Maths total score | 0.00 (−0.02 to 0.03) | 0.00 (−0.02 to 0.03) | 0.00 (−0.02 to 0.03) | |
| Science total score | 0.01 (−0.01 to 0.03) | 0.00 (−0.01 to 0.02) | 0.01 (−0.01 to 0.02) | |
| 25(OH)D2 | English total score | −0.07 (−0.10 to −0.04) | −0.05 (−0.08 to −0.02) | −0.05 (−0.08 to −0.01) |
| Maths total score | 0.02 (−0.01 to 0.06) | 0.03 (0.00 to 0.07) | 0.03 (0.00 to 0.06) | |
| Science total score | −0.03 (−0.06 to 0.01) | −0.01 (−0.05 to 0.02) | −0.01 (−0.05 to 0.02) | |
| Albumin-adjusted calcium | English total score | −0.01 (−0.03 to 0.01) | 0.00 (−0.01 to 0.02) | 0.01 (−0.01 to 0.03) |
| Maths total score | 0.00 (−0.02 to 0.02) | 0.01 (−0.01 to 0.03) | 0.01 (−0.01 to 0.03) | |
| Science total score | 0.00 (−0.03 to 0.02) | 0.01 (−0.01 to 0.03) | 0.00 (−0.02 to 0.02) | |
| Phosphate | English total score | 0.01 (−0.01 to 0.03) | 0.00 (−0.02 to 0.02) | 0.00 (−0.02 to 0.02) |
| Maths total score | 0.00 (−0.02 to 0.02) | −0.01 (−0.03 to 0.01) | −0.01 (−0.03 to 0.01) | |
| Science total score | 0.03 (0.01 to 0.05) | 0.02 (0.00 to 0.04) | 0.02 (−0.01 to 0.04) | |
| Parathyroid hormone | English total score | −0.01 (−0.03 to 0.01) | −0.02 (−0.04 to 0.00) | −0.02 (−0.04 to 0.00) |
| Maths total score | 0.00 (−0.02 to 0.03) | 0.00 (−0.02 to 0.03) | 0.01 (−0.02 to 0.03) | |
| Science total score | 0.00 (−0.02 to 0.02) | 0.00 (−0.02 to 0.02) | 0.00 (−0.02 to 0.02) | |
Model 1 is unadjusted (the exposures are standardised for age and gender and 25(OH)D3 is adjusted for season and ethnicity).
Model 2 same as model 1 plus adjustment for ethnicity, head of household social class, mothers and partners education, time spent outdoors during summer (age 8.5 years), use of sunblock, hat, covering clothing, avoidance of midday sun, body mass index and eligibility for free school meals.
Model 3 same as model 2 plus adjustment for serum concentrations of other hormones/metabolites, which are related 25(OH)D3 homoeostasis (eg, association of 25(OH)D3 is adjusted for 25(OH)D2, phosphate, albumin-adjusted calcium and parathyroid hormone).