All doctors depend on people who volunteer to participate in research. So do all patients. Without the volunteers, there could be almost no research, and without the research, how could anyone know which treatments are safe, let alone effective?

But researchers often struggle to recruit volunteers. As anyone who has tried to recruit patients to a clinical trial will know, you approach 100 and randomise perhaps 10, if you are lucky. This difficulty is prompting thought on what can be done to increase participation, and whether the public should be encouraged to see clinical research differently.

“Recruitment is probably the biggest challenge that clinical trialists face,” said Shaun Treweek, senior lecturer at the University of Dundee and assistant director of the Tayside Clinical Trials Unit.

“Difficulties with recruitment are very, very common, and some trials are just kicked into touch because they cannot recruit,” he added. “If you feel that there are areas where we should be doing more trials—and I do—then that needs even more people, and trialists are already struggling.”

A 2007 study of 114 multicentre trials funded by the UK’s Medical Research Council and Health Technology Assessment programme found that only a third kept up with their planned recruitment schedule.1

Recruitment problems don’t only mean more work and greater costs. Studies that don’t get enough volunteers might not record enough events to show a benefit, or detriment, while studies that miss “hard to recruit” patient groups generate results that are difficult to apply in real life.

Ethnic minorities are often poorly represented in published clinical trials.2 But Tom MacDonald, professor of clinical pharmacology and head of the University of Dundee’s Medicines Monitoring Unit, is keen …