Assessment of mental capacity: who can do it, or who should do it?

Schalk du Toit

I was interested to read about the discrepancy in the number of capacity assessments carried out by doctors on general adult and old age psychiatry wards (Singhal et al, Psychiatric Bulletin, January 2008, 32, 17-19). Although the authors gave no explanation, the result could be because in-patients on the general adult wards, who probably lacked capacity, were more likely to be detained under the Mental Health Act and therefore fell outside the Bournewood gap.

This result does however support my belief that doctors on general adult psychiatry wards do not assess their patient’s capacity (to consent to treatment) often enough.

I took part in a survey (Hill et al, 2006) in which consultant and trainee psychiatrists were asked, ‘What are the key elements in the assessment of a patient’s capacity?’ Over a third of the 95 participants could only identify two or less of the five points in testing decision-making capacity (Department of Health, 2005; Re C, 1994). This suggested an inadequate level of knowledge and I believe that as doctors we could become even more de-skilled, should we rely entirely on our nursing colleagues to fulfil this role in future.

The authors make the point that, ‘Appropriately trained mental health nursing staff can undertake this assessment.’ I am sure they can, but should they?

I believe it is appropriate that as prescribing doctors, we should be assessing our patient’s capacity to consent to the proposed treatment, and not merely delegate these duties to other healthcare professionals. This makes sense from an ethical and medico-legal perspective.