Fig. 2From: Evaluating the effect of vitamin D supplementation on serum levels of 25-hydroxy vitamin D, 1,25-dihydroxy vitamin D, parathyroid hormone and renin–angiotensin–aldosterone system: a systematic review and meta-analysis of clinical trialsFunnel plot and standard mean difference (SMD) of change of 25(OH)D in two groupsBack to article page