Introduction: Ageism is prevalent in clinical practice and research. Unjustified exclusion of older people and women from clinical trials occurs, despite political and legislative reform. This limits the generalisability of evidence.
Methods: We examined clinical research published in New England Journal of Medicine (NEJM), Circulation, British Medical Journal (BMJ) and Heart in 1981, 1991, 2001 and 2011. We excluded research on children and pregnancy. All original research papers were examined for mean age of study population, unjustified exclusion of older people and women recruited.
The mean age of study subjects included in research has increased significantly for all four journals in the last four decades (P < 0.001).
Unjustified exclusion of older people and women.
Percentage of studies with unjustified exclusion of older people and women shows a variable trend.
The two tables below show the percentage of studies excluding older people and the percentage of women included, respectively.
Conclusion: The mean age of research participants in published research is gradually increasing. Progress in including women in research has been variable and unjustified use of upper age exclusions persists.