Supplementary Material for: Racial, Ethnic, and Sex Disparities in Nail Psoriasis Clinical Trials: A Systematic Review

<b><i>Introduction:</i></b> Nail psoriasis (NP) disproportionally affects quality of life in females versus males. Demographics of NP research cohorts are not well characterized. In this systematic review, we characterize the representation of racial/ethnic groups and women in NP randomized clinical trials (RCTs). <b><i>Methods:</i></b> A systematic search of MEDLINE was performed; RCTs of NP pharmacologic treatments or cutaneous psoriasis/psoriatic arthritis with the number of NP patients described were included. <b><i>Results:</i></b> Overall, 45 RCTs were analyzed, with 91.1% reporting sex, and 67.9% of participants were men. 7/41 (17%) studies reporting sex included ≥45% female participants. Of 45 RCTs, 35.6% reported race and/or ethnicity. Of the 22 studies with ≥1 US-based site, 13 (59%) reported race/ethnicity; 3 out of 23 (13%) studies with &lt;1 US-based site reported these data. Enrollment of nonwhite participants was significantly lower than representation within the US census (13.4% vs. 39.9%; <i>p</i> &lt; 0.001). Treatment type, route of administration, location with ≥1 US-based site, funding, and journal type were significantly associated with race/ethnicity reporting (<i>p</i> &lt; 0.05 all comparisons). <b><i>Discussion/Conclusion:</i></b> Reporting of racial/ethnic demographics is lacking in NP RCTs. Women and racial/ethnic minorities remain underrepresented in NP research. There is a need for increased reporting and diversification of NP clinical trial participants.