The BMJ
['Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data.', 'High-Dose Monthly Vitamin D for Prevention of Acute Respiratory Infection in Older Long-Term Care Residents: A Randomized Clinical Trial.', 'Iwona Stelmach', 'The BMJ', 'Creative Commons Attribution', 'Vitamin D supplementation to prevent acute respiratory tract infections: systematic review and meta-analysis of individual participant data.']