How to increase the participation of older subjects in research: good practices and more evidence are needed!

Although the number of older subjects is rapidly increasing worldwide, they are still under-represented in research studies. This is true not only in pharmacological and non-pharmacological trials, but also in observational studies. Among the causes responsible for the lower representation of older subjects in research, particularly in clinical trials, there are explicit upper age limits or restrictive exclusion criteria, often poorly justified from a scientific point of view [1]. However, even when the researchers aim to include older subjects, there are difficulties in recruiting them as well as in maintaining them in the research projects, leading to lower enrolment and higher drop out rates in this population [2, 3]. Therefore, older participants are often younger, with less comorbidity and lower disability than...