Assessment of mental capacity in individuals with psychiatric disorders. (360G-Wellcome-075712_Z_04_A)

The project builds on previous work funded by Wellcome. Mental capacity is a cornerstone in the process of giving informed consent. The prevalence, associations and consequences of mental incapacity have not been sufficiently studied in clinical populations. Our first project involved acutely ill general hospital in-patients, and we determined that approximately 40% lacked mental capacity to make key treatment decisions. These patients were older and more cognitively impaired than patients who had mental capacity. We used transcripts of semi-structured interviews to determine that experts rating the interviews had good inter-rater reliability (mean kappa = 0.76). Our second study funded by Wellcome was the pilot study for the present proposal, and indicated firstly that two psychiatrists performing a semi-structured interview 1-2 days apart had good inter-rater reliability (kappa = 0.78). It also indicated that the proposed project is feasible, with satisfactory participation rates. The main aims are (1) To determine the prevalence of psychiatric in-patients who lack capacity to make key decisions regarding their treatment; (2) to test a series of hypotheses linking mental capacity with the use of the Mental Health Act, perceived coercion and the presence of cognitive impairment or delusions and (3) to describe the proportion of mentally incapacitated individuals who regain capacity by the time of discharge from hospital. A consecutive sample of 270 psychiatric in-patients will be approached and interviewed using the capacity interview, as well as measures of insight, perceived coercion, and clinical status. It will be possible from this study to determine the proportion of patients judged to lack mental capacity to make decisions regarding their current treatment. All incapacitated patients will be re-interviewed at the point of discharge, or six months following admission, to determine the proportion in whom capacity is regained over this period of time. Participants who are judged to lack capacity will be compared with those who are thought to have capacity on a range of clinical and demographic characteristics. We will then use univariate and multivariate statistical methods to compare these groups in terms of their legal status under the Mental Health Act (1983), their perception of coercion, and their insight into their condition.