Women are underrepresented in medical device clinical trials

Earlier this week, a research letter published in JAMA Internal Medicine evaluating female representation in randomized clinical trials for FDA-supervised medical devices found that women are generally underrepresented in these studies. The findings suggest that the guidance for female inclusion in medical device trials needs improvement.

The article was a systematic review of high-risk medical implant clinical trials from January 2016 to May 2022, focusing on gender representation across the trials. To calculate female representation, the researchers divided the number of women randomized by the total number of participants randomized. For trials that did not include that information, they looked at the number of women evaluated divided by the total number of individuals evaluated.

In addition, they calculated the participation-to-prevalence ratio (PPR) for each device as the percentage of women participating divided by women with the intervention in the general population.

Across the 195 clinical trials evaluated, the most common medical devices were cardiovascular or orthopedic, with stents, valves, and pacemakers as the most common devices overall.

Researchers found that the percentage of randomized women varied drastically across clinical trials, ranging from 7% to 100%. However, the median percentage of women randomized was approximately 33%, indicating underrepresentation.

Furthermore, the PPR values emphasize that women are underrepresented in medical device clinical trials, as the most common medical devices had PPR values under 0.8. For example, the PRP for stents was 0.77. Ratios were even lower for valves, orthopedic prostheses, and pumps at 0.76, 0.69, and 0.56, respectively.

Women’s representation in clinical trials has been a longitudinal challenge. Women were not even required to be included in clinical trials across the United States until the NIH inclusion policy was written into federal law in 1993.

Since this mandate, researchers, clinical trial leaders, and regulatory organizations have tried to expand diversity across all clinical trial participants. However, concerns about fetal consequences, underdiagnosis of women, perceived recruitment challenges, and clinical trial criteria favoring men pose challenges for female inclusion in trials.

To address these challenges, researchers in JAMA write: “Solutions proposed include equal enrollment of women to their share in the population with disease or planning a sample size that could detect gender differences. A study of trials of FDA-approved devices found minimal differences in efficacy or safety by gender. The most limiting step for women’s recruitment is the screening stage; higher awareness of physicians may improve enrollment. Women-led studies are more likely to include women. Stakeholders should consider implementing gender equity criteria for researchers involved.”

While certain limitations in this study hindered a comprehensive review of women’s representation in clinical trials, the data suggest that more efforts are needed to include women in medical device trials.