Conclusions Vitamin D supplementation  was safe and it protected against acute respiratory tract infection overall .
Patients who were very vitamin D deficient and those not receiving bolus doses experienced the most benefit .
Objectives To assess the overall effect of vitamin D supplementation on  risk of acute respiratory tract infection  , and to identify factors modifying this effect .
Improved control of childhood asthma with low‐dose, short‐term vitamin D supplementation: a randomized, double‐blind, placebo‐controlled trial
In our prior r and omized trial on preventing influenza , asthma attacks as a secondary outcome occurred less often in the vitamin D group than in the placebo group . We aim ed to clarify whether low‐dose , short‐term vitamin D supplementation , in addition to st and ard treatments , improves control of childhood asthma
Conclusions Vitamin D supplementation  was safe and it protected against acute respiratory tract infection overall .
Patients who were very vitamin D deficient and those not receiving bolus doses experienced the most benefit .
Objectives To assess the overall effect of vitamin D supplementation on  risk of acute respiratory tract infection  , and to identify factors modifying this effect .