This paper from the Canadian Health Services Research Foundation (CHSRF) outlines the process of 1:3:25 to structure research and evaluation reports.
1:3:25 refers to a format that can be used to provide a consistent structure for final reports of any kind. The option allows for a one page outline of the main messages that have come from the research, a three page executive summary and 25 pages to present the findings and methodology used in a language that is clear and accessible to the non-research specialist.
Canadian Health Services Research Foundation (CHSRF), (2001). Reader-friendly writing - 1:3:25. Retrieved from website: http://www.chsrf.ca/Migrated/PDF/CommunicationNotes/cn-1325_e.pdf