Heart failure (HF) is a leading cause of hospitalisation, morbidity, and mortality in men and women, accounting for 46 076 annual HF deaths in women and 2.6 million women living with HF between 2015 and 2018 in the USA. Sex differences across the HF spectrum are well defined and pertain to risk factors, aetiology, provision of evidence-based therapies, referral to services, treatment response and clinical outcomes in both the acute and chronic HF syndrome setting.1

Much of our evidence base for the management of HF is derived from randomised clinical trials (RCTs) that inform best practice for the treatment of HF and shape guideline recommendations. The value of such trials in informing the management of HF in both men and women depends on representativeness of trial populations. Underenrolment of women in HF trials is well documented, including in landmark trials that have informed care.1–4 Since 2000, multiple studies have examined the recruitment of women in HF RCTs and reported that enrolment of women has varied between 21% and 29%,1–5 which is significantly below the prevalence of HF at the population level. In an attempt to quantify the representativeness in trials, recent studies have used the ratio of trial participation to disease prevalence ratio (PPR). A PPR <0.8 is considered low and indicates underrepresentation. A recent analysis of 740 cardiovascular trials (102 trials in HF) registered between 2010 and 2017 has shown the lowest PPR of 0.48 in HF trials.5 This is despite the fact that legislature such as the National Institutes of Health …