Reporting and Representativeness of Race, Ethnicity, and Socioeconomic Status in Systemic Sclerosis Randomized...

To assess how and to what extent socioeconomic status and ethnicity/race of participants are reported in randomized controlled trials (RCTs) on systemic sclerosis (SSc), and to estimate the representativeness of different ethnic/racial groups in SSc RCTs.

We searched all published RCTs on SSc indexed in PubMed. We retrieved information on main features of RCTs published from 2000 onward and recorded for each study whether race/ethnicity was reported; how ethnicity/race was defined and assigned; and the number of patients included for each racial/ethnic group. Multivariable logistic regression was used to identify factors associated with race/ethnicity reporting. Proportion of races/ethnicities included in US-based RCTs on SSc was examined and compared with US demographic data.

We included 106 studies, mostly conducted in Europe (42%) or North America (25%), published after 2010 (74%), and enrolling a total of 6,693 patients. About one-third of studies provided information about race/ethnicity, with no improved reporting over time. Only 2 papers reported patient's socioeconomic status. Study location (US or intercontinental) was the only significant factor associated with a better reporting of race/ethnicity in multivariable analysis. In studies where race/ethnicity was reported, White patients were mostly represented (79%), followed by Asian (7%), and African American (6%). In the sensitivity analysis limited to studies from the US, underrepresentation of African American patients was observed in the 2000-2010 time period, but not later.

Documentation of race/ethnicity and socioeconomic status is poor in RCTs on SSc. More effort should be made to document race/ethnicity and socioeconomic status and to promote diversity in SSc RCTs.