Despite the high frequency of cardiovascular diseases in women, female participants counted for less than 40 percent of researches in the last decade. A review of women’s participation in cardiovascular trails from 2010 to 2017, published in the American Heart Association journal, Circulation, found that male participation predominates overall. Female participation varies according to trial characteristics and disease. Although still underrepresented, it has improved in the case of stroke and heart failure trials. 
The researchers used data from cardiovascular trials registered with the ClinicalTrials.gov. In all, they studied 740 completed trials with a total of 862 652 adults. They considered factors like disease type, sponsor, country, intervention type, trial size and the demographics of the participants. The female-to-male ratio was calculated for each trial. They also considered the prevalence of the disease in the disease population, also known as the participation prevalence ratio.
The team found that the overall participation of women was 38.2 percent. The median female-to-male ratio on an average was 0.51 overall. It varied by age group, type of intervention, disease type, region, sponsor type, and trial size. Participation was higher in women up to 55 years of age than 61-65 years age group, for lifestyle intervention trials than procedural trials, for pulmonary hypertension than an acute coronary syndrome, for multiple sponsors when compared to government-funded studies, for smaller trials and lower in the Western Pacific region.
The participation prevalence ratio was in the healthy range for hypertension and pulmonary arterial hypertension. However, it was low for arrhythmia, acute coronary syndrome, heart failure trials, and coronary heart disease.