Table 2.
Effect of being randomised to vitamin D supplementation on PIQ-6 score, presence of some or more pain impact and presence of some bodily pain
| PIQ-6 score, mean | sd | Some or more pain impact*, n | % | Some bodily pain, n | % | |
|---|---|---|---|---|---|---|
| Year 1 | ||||||
| Vitamin D (n 9733) | 50·4 | 9·8 | 5008 | 51·5 | 4836 | 48·2 |
| Placebo (n 9658) | 50·4 | 9·7 | 4907 | 50·8 | 4751 | 47·6 |
| Effect estimate (95 % CI)†,‡ | 0·04 | −0·23, 0·31‖ | 1·01 | 0·99, 1·04¶ | 1·01 | 0·98, 1·04¶ |
| Year 2 | ||||||
| Vitamin D (n 7630) | 50·3 | 9·8 | 3893 | 51·0 | 3926 | 49·5 |
| Placebo (n 7550) | 50·4 | 9·9 | 3878 | 51·4 | 3864 | 49·1 |
| Effect estimate (95 % CI)†,‡ | −0·17 | −0·48, 0·14‖ | 0·99 | 0·96, 1·02¶ | 1·01 | 0·98, 1·04¶ |
| Year 5 | ||||||
| Vitamin D (n 9164) | 49·9 | 8·9 | 3982 | 43·5 | 4255 | 46·2 |
| Placebo (n 9029) | 49·8 | 8·7 | 3840 | 42·5 | 4131 | 45·5 |
| Effect estimate (95 % CI)†,‡ | 0·08 | −0·17, 0·34‖ | 1·02 | 0·99, 1·06¶ | 1·01 | 0·98, 1·05¶ |
| Overall effect estimate (95 % CI)§ | 0·02 | −0·20, 0·25 | 1·01 | 0·99, 1·03 | 1·01 | 0·99, 1·03 |
PIQ, Pain Impact Questionnaire.
*
Some or more pain impact: PIQ-6 score >50.
†
Effect estimates comparing vitamin D with placebo (reference).
‡
Effect estimates adjusted for age, sex and state.
§
Effect estimate calculated using all available records; generalised estimating equations with exchangeable correlation matrix used to account for intra-person correlation.
‖
Adjusted mean difference (95 % CI) estimated using linear regression.
¶
Adjusted prevalence ratio (95 % CI) calculated using log-linked binomial regression.