Table 3.

Mean radial BMD z-scores at 1-, 2- and 3-year follow-up by allocation: overall and by sub-group

			Vitamin D arm: mean value (s.d.) [n]	Placebo arm: mean value (s.d.) [n]	Adjusted mean difference (95% CI)(1)	P for timepoint	Overall P(2)	P for interaction
Overall		1 year	−0.79 (1.22) [668]	−0.88 (1.18) [680]	0.08 (−0.04 to 0.21)	0.19	0.11	--
		2 years	−1.06 (1.27) [629]	−0.99 (1.17) [649]	−0.06 (−0.19 to 0.07)	0.35
		3 years	−0.96 (1.22) [671]	−0.92 (1.19) [686]	−0.06 (−0.18 to 0.07)	0.36
By sex	Male	1 year	−0.80 (1.26) [339]	−0.89 (1.22) [353]	0.07 (−0.11 to 0.25)	0.44	0.19	0.90
		2 years	−1.03 (1.27) [322]	−1.04 (1.18) [332]	−0.01 (−0.19 to 0.17)	0.91
		3 years	−1.11 (1.28) [336]	−1.02 (1.21) [358]	−0.13 (−0.31 to 0.05)	0.14
	Female	1 year	−0.77 (1.19) [329]	−0.86 (1.14) [327]	0.09 (−0.08 to 0.27)	0.29	0.27
		2 years	−1.09 (1.26) [307]	−0.95 (1.17) [317]	−0.12 (−0.3 to 0.06)	0.19
		3 years	−0.80 (1.14) [335]	−0.80 (1.15) [328]	0.01 (−0.17 to 0.18)	0.95
By baseline 25(OH)D concentration	<10 ng/ml	1 year	−0.81 (1.18) [233]	−0.87 (1.11) [254]	0.05 (−0.16 to 0.25)	0.66	0.57	0.87
		2 years	−1.09 (1.23) [217]	−1.06 (1.24) [241]	−0.02 (−0.23 to 0.19)	0.86
		3 years	−1.03 (1.20) [232]	−0.95 (1.16) [255]	−0.08 (−0.29 to 0.12)	0.42
	≥10 ng/ml	1 year	−0.77 (1.25) [435]	−0.88 (1.22) [426]	0.12 (−0.04 to 0.27)	0.14	0.18
		2 years	−1.04 (1.29) [412]	−0.95 (1.13) [408]	−0.07 (−0.23 to 0.08)	0.36
		3 years	−0.92 (1.23) [439]	−0.89 (1.2) [431]	−0.04 (−0.19 to 0.12)	0.65
By calcium intake	<500 mg/day	1 year	−0.77 (1.23) [423]	−0.91 (1.19) [409]	0.14 (−0.02 to 0.30)	0.09	0.15	0.16
		2 years	−1.02 (1.24) [406]	−1.02 (1.18) [401]	0.01 (−0.15 to 0.17)	0.89
		3 years	−0.97 (1.22) [441]	−0.98 (1.22) [431]	0 (−0.15 to 0.16)	0.95
	≥500 mg/day	1 year	−0.84 (1.20) [223]	−0.86 (1.13) [237]	0.03 (−0.18 to 0.24)	0.80	0.63
		2 years	−1.12 (1.34) [213]	−0.96 (1.17) [235]	−0.12 (−0.33 to 0.09)	0.27
		3 years	−0.91 (1.22) [222]	−0.81 (1.13) [245]	−0.09 (−0.30 to 0.12)	0.39

Abbreviations: 25(OH)D₃, 25-hydroxyvitamin D₃. BMD, bone mineral density. CI, confidence interval. S.d., standard deviation. N, number.

^1,adjusted for baseline value and school of attendance.

^2,deseasonalized values.