[Evaluation of psychosocial interventions for dementia: what to learn from the Cochrane Library?].

Psychosocial interventions for people with dementia have expanded in the last decades, and have been subject to an important number of evaluation attempts that often lead to scientifically flaw results. To study these failures we analysed the meta-analyses of the Cochrane Library. Among 18 meta-analyses, 11 were selected for the purpose of this study. These papers were analysed on the basis of the Cochrane selection criteria, methodological quality and biases, principal outcomes and implication for practice and research. Results are discussed and analysed according to the clinical practice and scientific literature of the matter of concern. Main outcomes of this review point that: (1) it is necessary to adopt an investigation methodology adapted to specific characteristics of psychosocial interventions; (2) methodological weaknesses of randomised control trials are prejudicial to quality of research and clinical practice; (3) implementation of randomised control trials call for necessary fundamental prerequisites; and (4) other research methods than randomised control trials are susceptible to give as much, if not more, informative results. A research and practice implementation strategy is suggested.