Fig. 1From: Vitamin D supplementation to patients with frequent respiratory tract infections: a post hoc analysis of a randomized and placebo-controlled trialTime to first acute respiratory tract infection (RTI) in immunodeficient patients treated with vitamin D (4000 IE/day for 1 year) or placebo. There was a significantly higher probability to stay infection free in the vitamin D-group (HR 1.68, 95 % CI 1.03–2.68, p = 0.038, Log rank Mantel Cox test)Back to article page