Bacillus Calmette-Guérin vaccine to reduce COVID-19 infections and hospitalisations in healthcare workers – a living systematic review and prospective ALL-IN meta-analysis of individual participant data from randomised controlled trials

Abstract

The ALL-IN-META-BCG-CORONA project is a prospective, living meta-analysis of clinical trials examining whether the BCG vaccine offers protection against COVID-19. It introduced a bottom-up approach to meta-analysis, emphasizing equal collaboration among all trial teams. The resulting open-access paper includes a comprehensive replication package designed to support reuse, transparency, and proper crediting of contributors. Although its goal to make supplementary materials and individual contributions more visible through platforms like ResearchEquals fell short due to citation limitations on platforms like Google Scholar and PubMed, the initiative offers valuable lessons for the open science community.