Proposed criteria for reporting the development and evaluation of complex interventions in healthcare (CReDECI): guideline development.

Methods of research on complex interventions have received increasing awareness in nursing and health care science. The British Medical Research Council's (MRC) framework on the development and evaluation of complex interventions has been widely applied. It does, however, not specifically support authors to comprehensively and transparently report their complex study to ensure interpretation of study results and replicability of the intervention. So far, no reporting criteria for the development and evaluation of complex interventions have been published. Based on the updated MRC framework and corresponding methodological literature, a set of criteria on the reporting and evaluation of complex interventions has been developed and reviewed by experts in the field. As a result, a criteria list comprising 16 items has been created covering the first three stages of the MRC framework: (1) development; (2) feasibility and piloting; and (3) introduction of the intervention and evaluation. The list provides a minimum standard of criteria necessary to ensure high quality reporting of studies on the development and evaluation of complex interventions. In a final step, the reporting criteria on complex interventions have to pass a formal consensus process according to the methods recommended by the EQUATOR network.