Table 5. Odds ratio and 95% CI for low and normal ferritin groups according to serum vitamin D levels.

CI: confidence interval

Vitamin D levels	Ferritin of <12 ng/ml	Ferritin of >12 ng/ml	Odds ratio
Vitamin D deficiency	23	24	9.6 (95% CI: 1.1–80.9, p=0.019)
Vitamin D insufficiency	3	10