Analysis of NICE guidelines demonstrates the need for improved consideration of sex and gender in healthcare

Published

Women are 50% more likely than men to be misdiagnosed following a heart attack. Men face higher mortality after hip fractures. Trans and non-binary patients frequently report that clinicians lack knowledge of their health needs. These inequities are compounded if clinical guidelines, intended to reduce bias and to standardise care, do not address them. So how effective are guidelines at addressing sex and gender differences in healthcare?

Clinical guidelines help healthcare providers to make consistent, evidence-based decisions for their patients, shaping diagnosis, treatment and care. In England and Wales, national guidelines are produced by the National Institute for Health and Care Excellence (NICE), a public body sponsored by the Department of Health and Social Care.

In 2024-25, the MESSAGE team reviewed all available NICE clinical guidelines to examine how they account for sex and gender differences. Sex and gender play an important role in health and illness across all conditions, including but not limited to cardiovascular disease, dementia, autoimmune disorders and mental health. Yet these variables are often overlooked in research and clinical practice. The study, published in BMJ Public Health, reveals considerable sex and gender gaps in clinical guidelines, which will impact the care that patients receive. Of the 197 eligible guidelines:

  • Just one guideline provided evidence-based recommendations separately for women and men (this was focused on addressing infertility).
  • Nearly 40% of guidelines contained no mention of sex or gender at all.
  • Only 41% of guidelines referenced sex and/or gender outside of pregnancy and childbirth.
  • 75% of guidelines did not consider sex and gender beyond the binary of female/male or woman/man.

The male default

When sex and gender differences were mentioned, information provided was often limited. Strikingly, when evidence gaps for male patients existed, such as in breast cancer, guidelines tended to acknowledge this explicitly. No similar acknowledgement was found when evidence was missing for female patients, reflecting a persistent ‘male default’ in medical research. Likewise, some guidelines noted that treatment should differ for female patients, but did not explain what those different treatments should be.

‘Bikini medicine’[1]

A recurring theme was how often sex and gender considerations were only mentioned in the context of women’s reproductive health, often referred to as ‘bikini medicine’. Female-specific treatment advice was frequently limited to considerations around pregnancy, childbearing and breastfeeding, and we found several instances where guidelines listed medications that patients should avoid whilst pregnant, without providing information on what treatment should be given instead. In this way, guidelines risk reinforcing the outdated view that women’s health is synonymous with reproductive health. Likewise, sex-related considerations for men were also often limited to fertility or erectile dysfunction, overlooking differences in broader disease risk and outcomes.

Sex and gender beyond the binary

Only eight guidelines made any reference to trans, non-binary or intersex people, despite these groups experiencing distinct health needs and disproportionate inequities in care. Where guidelines did acknowledge diverse identities, they provided definitions of terminology and practical, inclusive recommendations. For example, the guideline surrounding cardiovascular disease advises that risk should be calculated based on both sex assigned at birth and gender for patients who have undergone gender reassignment. However, such examples were rare. Most guidelines conflated sex and gender terminology, or used gendered language to describe biological differences, creating both scientific inaccuracies and barriers to inclusive care.

Gender of committee members

The review explored the correlation between the gender of guideline committee members and chairs, and how well guidelines accounted for sex and gender. The vast majority of committees were chaired by men whilst the majority of lay representatives were women, mirroring the healthcare sector more broadly where women constitute most of the workforce but are significantly under-represented in positions of power and leadership. Notably, we found that guidelines chaired by women scored better for sex and gender inclusion than those chaired by men. This pattern reflects other studies which highlight that greater gender diversity in leadership is likely to lead to a wider range of patient needs and experiences being accounted for in practice.

Implications

Failing to properly integrate sex and gender into clinical guidelines has significant consequences. For patients, it can mean delayed diagnoses, inappropriate treatments and poorer health outcomes. For clinicians, vague guidance means more uncertainty in decision-making, especially in time-pressured environments like emergency departments or primary care. The NHS has long championed the goal of personalised medicine; when diagnostic tests, treatment thresholds and risk scores are adjusted for sex, everyone benefits. In order to represent the gold standard of care, clinical guidelines must reflect the realities of sex and gender in health, not as an afterthought, but as a fundamental part of evidence-based medicine.

NICE is uniquely positioned to initiate change. Unlike many countries and their health systems, where clinical guideline development is fragmented across multiple organisations, NICE acts as the single focal point for England and Wales (and to an extent, Scotland), providing a powerful opportunity to embed sex- and gender-disaggregated evidence across the board.

The study provides several recommendations of changes that NICE must adopt to urgently address sex and gender gaps. These include:

  • Implement a consistent, routine process to ensure that sex and gender considerations are embedded in the creation of all future guidelines, including a compulsory question regarding consideration of sex and gender in guideline consultations.
  • Identify the sex and gender data gaps in existing clinical guidelines, and integrate existing high-quality research into guidelines. This should include a large-scale consultation, a systematic review of existing research and engagement with experts, followed by publishing clear recommendations on the most urgent evidence gaps.
  • Employ clearer terminology to avoid confusion between sex and gender, and to be inclusive of non-binary and trans populations.
  • Ensure more diverse leadership in guideline committees.

You can read the full BMJ Public Health article here.

[1] The term ‘bikini medicine’ was coined in the 1980s by Dr Nanette Wenger, a cardiologist seeking to expand the notion of women’s healthcare beyond sexual and reproductive health.