1. Vitamin D: increasing supplement use in at-risk groups—guidance and guidelines;National Institute for Health and Care Excellence,2014
2. Dietary supplement use among U.S. adults has increased since NHANES III (1988-1994);Gahche;NCHS Data Brief,2011
3. Vitamin D metabolism, mechanism of action, and clinical applications;Bikle;Chem Biol,2014
4. Vitamin D insufficiency;Thacher;Mayo Clin Proc,2011
5. Vitamin D status and its association with season, hospital, and sepsis mortality in critical illness;Amrein;Crit Care,2014