Clinical trials in older people.

Randomised controlled trials (RCTs) usually provide the best evidence for treatments and management. Historically, older people have often been excluded from clinical medication trials due to age, multimorbidity and disabilities. The situation is improving, but still the external validity of many trials may be questioned. Individuals participating in trials are generally less complex than many patients seen in geriatric clinics. Recruitment and retention of older participants are particular challenges in clinical trials. Multiple channels are needed for successful recruitment, and especially individuals experiencing frailty, multimorbidity and disabilities require support to participate. Cognitive decline is common, and often proxies are needed to sign informed consent forms. Older people may fall ill or become tired during the trial, and therefore, special support and empathic study personnel are necessary for the successful retention of participants. Besides the risk of participants dropping out, several other pitfalls may result in underestimating or overestimating the intervention effects. In nonpharmacological trials, imperfect blinding is often unavoidable. Interventions must be designed intensively and be long enough to reveal differences between the intervention and control groups, as control participants must still receive the best normal care available. Outcome measures should be relevant to older people, sensitive to change and targeted to the specific population in the trial. Missing values in measurements are common and should be accounted for when designing the trial. Despite the obstacles, RCTs in geriatrics must be promoted. Reliable evidence is needed for the successful treatment, management and care of older people.