Measuring the data gap: inclusion of sex and gender reporting in diabetes research

BACKGROUND: Important sex and gender differences have been found in research on diabetes complications and treatment. Reporting on whether and how sex and gender impact research findings is crucial for developing tailored diabetes care strategies. To analyze the extent to which this information is available in current diabetes research, we examined original investigations on diabetes for the integration of sex and gender in study reporting. METHODS: We examined original investigations on diabetes published between January 1 and December 31, 2015, in the top five general medicine journals and top five diabetes-specific journals (by 2015 impact factor). Data were extracted on sex and gender integration across seven article sections: title, abstract, introduction, methods, results, discussion, and limitations. RESULTS: We identified 155 original investigations on diabetes, including 115 randomized controlled trials (RCTs) and 40 observational studies. Sex and gender were rarely incorporated in article titles, abstracts and introductions. Most methods sections did not describe plans for sex/gender analyses; 47 (30.3%) articles described plans to control for sex/gender in the analysis and 12 (7.7%) described plans to stratify results by sex/gender. While most articles (151, 97.4%) reported the sex/gender of study participants, only 10 (6.5%) of all articles reported all study outcomes separately by sex/gender. Discussion of sex-related issues was incorporated into 21 (13.5%) original investigations; however, just 1 (0.6%) discussed gender-related issues. Comparison by journal type (general medicine vs. diabetes specific) yielded only minor differences from the overall integration results. In contrast, RCTs performed more poorly on multiple sex/gender assessment metrics compared to observational studies. CONCLUSIONS: Sex and gender are poorly integrated in current diabetes original investigations, suggesting that substantial improvements in sex and gender data reporting are needed to inform the evidence to support sex- and gender-specific diabetes care.