Table 2

Mean serum concentrations (nmol/l) of 25 hydroxy vitamin D and the prevalence of profound (<25 nmol/l) and moderate (<40 and <75 nmol/l) vitamin D deficiency, overall and by season of measurement

	N	Mean^*	SD
Overall	1197	41.8	1.6
Winter	307	35.6	1.6
Spring	375	35.7	1.6
Summer	189	55.0	1.5
Autumn	326	49.6	1.5
Overall	Total N	N	%
<25 nmol/l		195	16.3
≥25 and <40 nmol/l	1197	328	27.4
≥40 and <75 mol/l		534	44.6
≥75 nmol/l		140	11.7
Winter and spring
<25 nmol/l		172	25.2
≥25 and <40 nmol/l	682	218	32.0
≥40 and <75 nmol/l		251	36.8
≥75 nmol/l		41	6.0
Summer and autumn
<25 nmol/l		23	4.5
≥25 and <40 nmol/l	515	110	21.4
≥40 and <75 nmol/l		283	55.0
≥75 nmol/l		99	19.2

↵* Geometric mean.