Racial, Ethnic and Sex Representation in Tourette's Syndrome Clinical Trials: A Meta-Analysis.

BACKGROUND

Equitable representation in clinical trials is essential to informing evidence-based treatment and reducing health disparities. No evidence is available about racial, ethnic and sex representation in Tourette's Syndrome (TS) treatment trials.

OBJECTIVES

To evaluate racial, ethnic and sex representation in randomized controlled trials (RCTs) of TS medications.

METHODS

We searched CENTRAL, Embase, PsycINFO, PubMed, Web of Science Core Collection and ClinicalTrials.gov for TS RCTs conducted in the US. The primary outcome was participation-to-prevalence ratio (PPR), the proportion of trial participants in racial, ethnic and sex subgroups divided by the proportion of individuals in the corresponding subgroup in the US population. Data were pooled through random-effects meta-analysis. Temporal trends were explored using meta-regression.

RESULTS

Overall, 40 RCTs involving 1717 participants were included. All trials reported sex, but only 22 (55%) and 12 (30%) provided race and ethnicity data, respectively. Reporting of race and ethnicity improved over time (meta-regression coefficient (b) 1.80, 95% confidence interval [CI] 0.62-2.98 per decade, P = 0.002). Asian (PPR 0.46, 95% CI 0.29-0.75, P = 0.002), Black (PPR 0.44, 95% CI 0.34-0.57, P < 0.001), Hispanic (PPR 0.41, 95% CI 0.27-0.64, P < 0.001) and female (PPR 0.75, 95% CI 0.65-0.85, P < 0.001) individuals were underrepresented. Only Hispanic enrollment improved over time (b 0.78, 95% CI 0.35-1.20 per decade, P < 0.001).

CONCLUSIONS

There are disparities in racial, ethnic and sex representation in RCTs of TS medications. Under-enrollment of minority participants may reflect disparities in terms of actual diagnosis of the condition, recruitment of minority individuals for participation in research studies or both.