PROTOCOL: Mass deworming for improving health and cognition of children in endemic helminth areas: a systematic review and individual participant data network meta‐analysis. Issue 1 (18th April 2018) - Welch, Vivian; Ghogomu, Elizabeth; Hossain, Alomgir; Arora, Paul; Cousens, Simon; Gaffey, Michelle; Riddle, Alison; Salam, Rehana; Tugwell, Peter; Bhutta, Zulfiqar; Wells, George A; ,