Under-Enrollment of Women in Stroke Clinical Trials: What Are the Causes and What Should Be Done About It?

The under-representation of women in clinical trials is a commonly recognized and seemingly intractable problem in many different areas of clinical medicine. Discrepancies in the enrollment of women in clinical trials raises concerns about the generalizability of trial evidence, as well as the potential for reduced access and utilization of new therapies in women. Recent studies confirm that the problem of under-enrollment of women continues to exist in stroke clinical trials, even after accounting for the sex ratio of stroke cases in the underlying population. The origins of these disparities are complex, and there remains a relative dearth of stroke studies that have examined the causes in detail. Although caution should be used when generalizing research findings from studies conducted in other medical conditions including cardiology trials, factors that contribute to lower enrollment in women include the use of specific trial eligibility criteria (eg, older age, presence of specific comorbidities), patient attitudes and beliefs (resulting in less interest and more refusals in women), and potentially implicit biases among study personnel. Beyond a general call to prioritize stroke research in this area, we also recommend the greater use of trial screening logs, the use of qualitative studies to understand patient attitudes and beliefs towards stroke research, avoiding the use of age-based exclusion criteria (eg, >80 years), and increasing the number of women who lead stroke clinical trials.