Ascertaining capacity to consent: a survey of approaches used by psychiatrists

Doctors are increasingly criticised for imposing treatment without adequate consent. Approaches used by psychiatrists (of all grades and in all sub-specialities) to assess capacity to consent in a large west London psychiatric trust were surveyed with a questionnaire. The questionnaire consisted of two case-vignettes and a series of seven questions (six with forced choice yes/no answers and one with an open-ended answer). The responding psychiatrists' assessment of capacity and that judged by the research psychiatrist were compared. There was no relationship between age, sex, duration of experience in psychiatry, grade and speciality, and (i) the respondents' assessment of capacity and (ii) the research psychiatrist's assessment of capacity. The kappa concordance between the responding psychiatrists' assessment of capacity and that judged by the research psychiatrist was 0.17 (P=0.067) and 0.12 (P>0.05) for vignettes 1 and 2 respectively. Individual psychiatrists appear to variably interpret and apply the criteria for assessment of capacity to consent.