Table 3– Year 5 plasma 25-hydroxyvitamin D (25(OH)D) levels by season
CharacteristicWinterSpringSummerAutumn
Participants48515740
25(OH)D ng·mL−118.3±7.024.1±10.331.7±9.226.8±9.6
Normal vitamin D level#2 (4)16 (31)34 (60)15 (38)
Vitamin D-insufficient19 (40)15 (29)20 (35)15 (38)
Vitamin D-deficient+27 (56)20 (39)3 (5)10 (25)
  • Data are presented as n, mean±sd or n (%). Seasons were defined as winter (January–March), spring (April–June), summer (July–September) and autumn (October–December). See figure 1 for p-values from pairwise statistical testing of mean 25(OH)D levels by season. #: ≥30 ng·mL−1; : ≥20 but <30 ng·mL−1; +: <20 ng·mL−1.