Why Secondary Analyses in Vitamin D Clinical Trials Are Important and How to Improve Vitamin D Clinical Trial Outcome Analyses-A Comment on "Extra-Skeletal Effects of Vitamin D, Nutrients 2019, 11, 1460"

Nutrients. 2019 Sep 11;11(9):2182. doi: 10.3390/nu11092182.

¹ Sunlight, Nutrition, and Health Research Center, P.O. Box 641603, San Francisco, CA 94164-1603, USA. wbgrant@infionline.net.
² The Blizard Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London E1 4NS, UK. bboucher@doctors.org.uk.

Abstract

Dear Editor, [...].

Keywords: D2d; VITAL; cancer; diabetes mellitus; randomized controlled trial; secondary outcomes; supplementation; vitamin D.