Responses from research training needs surveys, session evaluations from research training workshops, and eLearning feedback collected between 2017 and 2019 from 7176 participants from across 153 countries were analysed. This analysis provided a range of research skills topics and subject areas that generated a core list of 98 potential essential research skills training themes. These potential themes were reviewed by health research experts and stakeholders through a Delphi consensus process to assess their relevance as an essential research skill.