RESUMEN
OBJECTIVE: To assess the use of evidence-based research (EBR) approach in randomized controlled trials (RCTs) of acupuncture-related therapies for primary dysmenorrhea (PD). METHODS: PubMed, EMBASE, Cochrane Library, China National Knowledge Infrastructure, Wanfang Database, Chinese Biomedical Database, and China Science and Technology Journal Database were searched from January 2013 to December 2022 for RCTs of acupuncture on PD. The full text and references of each RCT were read to assess whether systematic reviews (SRs) or other types of studies with similar research questions and end-users' perspectives were cited to justify and design the trial. In addition, the discussion section were analyzed to evaluate whether trials placed the new result in the existing SRs to draw a conclusion. Multivariable logistic regression was used to find variables that associated with 3 aspects of EBR approach: (1) citing clinical studies for justification, (2) citing relevant studies that obtain the perspectives of end users, and (3) citing clinical studies for results discussion. RESULTS: Of 473 RCTs included, 45.67% (216) of the trials cited relevant similar studies, 21.56% (102) referenced to the studies that collected end-users' perspectives, and 10.99% (52) placed result in the context of the previous research. Few RCTs appropriately applied EBR approach. Among all the included studies, 3.17% (15) of the trials used SRs to inform study questions but none of them used updated SRs with acceptable quality; 1.05% (5) of the trials cited SRs of end-user's perspectives in the justification and design of the study, and only 1 trial added results in existing SR to draw a conclusion. Year of publication, language, funding, registration, ethical approval and number of sites were significantly associated with 1 of the 3 aspects of EBR approach. CONCLUSIONS: Few RCTs in acupuncture-related therapies for PD used the EBR approach to minimize research redundancy. Researchers, research institutes, funding agencies, ethics committees, journals and peer reviewers in acupuncture should make efforts to use and promote the EBR approach to ensure the value of new trials.