Abstract
Background The Mental Capacity Act 2005 of England and Wales is a ground-breaking piece of legislation with reach into healthcare, social care and legal settings. Professionals have needed to develop skills to assess mental capacity and handle malign influence, but it is unclear how assessments are implemented in real world settings. Our previously reported survey found professionals juggling competing resources in complex systems, often struggling to stay up to date with law. The current follow-up study uses one-to-one interviews of professionals to characterise in detail six areas of uncertainty faced when assessing mental capacity, whilst suggesting ways to make improvements. Methods Forty-four healthcare, social care and legal professionals were interviewed, using a semi-structured topic guide. Transcripts were analysed using framework analysis: a qualitative technique built to investigate healthcare policy. Results Our topic guide generated 21 themes. In relation to the six areas of uncertainty: 1) Many participants stressed the importance of capturing a holistic view, adding that their own profession was best-placed for this - although a medical diagnosis was often needed. 2) The presumption of capacity was a laudable aim, though not always easy to operationalise and occasionally being open to abuse. 3) There was cautious interest in psychometric testing, providing a cognitive context for decisions. 4) Undue influence was infrequent, but remained under-emphasised in training. 5) Multi-professional assessments were common, despite doubts about fitting these within local resources and the law. 6) Remote assessment was generally acceptable, if inadequate for identifying coercion. Conclusions Practical constraints and competing demands were reported by professionals working within real world systems. Assessment processes must be versatile, equally applicable in routine and emergency settings, across diverse decisional types, for both generalist and specialist assessors, and able to handle coercion. Recognising these challenges will guide development of best practices in assessment and associated policy.