The definition of capacity given in the Mental Capacity Act for England and Wales (2005) is that, at the time a decision needs to be made, a person is able to understand the information relevant to the decision, retain that information, use or weigh that information as part of the process of making the decision, and communicate his decision (whether by talking, using sign language or any other means).

Capacity is specific to the task in hand. In ambiguous circumstances the risks associated with the decision must be proportionate to the degree of certainty of the person's capacity, a ‘sliding scale’ of capacity (Reference StoneStone, 1994). The assessment of capacity is subjective and can be complex.

Doctors are often asked or take upon themselves to evaluate the ability of older adults to continue living alone in the community; their capacity to make this decision can be more difficult to assess than that for other medical dilemmas. A large number of requests for capacity assessments of medical in-patients are seen in liaison psychiatric services for older people (Reference Mujic, Hanlon and SullivanMujic et al, 2004): the role of the psychiatrist should be to assess the degree of impairment that may affect capacity. The assessment of the capacity of older people to consent to permanently enter a care home is a major issue. Pressure on beds may preclude both older people and their carers from exercising a genuinely informed choice (Reference Lundh, Sandberg and NolanLundh et al, 2000). It is usually a family member who takes the lead in both the decision to seek and find a care home, but surrogates may frequently misunderstand patient preferences in relation to living permanently in a nursing home (Reference Mattimore, Wenger and DesbiensMattimore et al, 1997). The person undertaking the intervention should explain it and assess capacity, in this case the social worker involved. Healy (Reference Healy2003) has examined, in a qualitative study, social workers’ ethical tension as they evaluate decisional capacity of older individuals experiencing some degree of cognitive impairment. Ethical tension was particularly strong when participants experienced both pressures from professionals and clinical uncertainty.

Attempts have been made to systematise the assessment of capacity, most prominently the MacArthur Competency Assessment Tool (MacCAT), which can be used in most US jurisdictions (Reference Appelbaum and GrissoAppelbaum & Grisso, 1995). Measurable subcomponents (understanding, appreciation, reasoning, and ability to express a choice) are assessed. Its use has been reported in decisions about treatment by working-age psychiatric patients in the UK (Reference Cairns, Maddock and BuchananCairns et al, 2005); however, it remains unvalidated in these jurisdictions and its use has not been reported in older people in the UK at all, let alone in those with cognitive impairment.

The assessment is longer than would normally be feasible in busy medical wards for older people. We therefore developed a clinical algorithm that has been previously used in older people in nursing homes (Reference Macdonald, Roberts and CarpenterMacdonald et al, 2004) for use in this setting. It was based on the principles outlined by the Law Commission (Law Commission, 1996) and conformed with those outlined in the Mental Capacity Act (2005) which received Royal Assent during the study. We wished to investigate the feasibility of its use and the relationship between its results and the assessments of capacity by doctors, nurses and social workers involved in the decision of an older patient to permanently enter a care home from acute medical wards for older people. We hypothesised that a high proportion of patients confronted with this decision would be cognitively impaired, and that less than 10% of older people entering a care home would have a recorded assessment of their capacity to consent to placement in the medical, social work or nursing documentation.

Method

All people over 65 years old on all acute general medicine for older people wards of a district general hospital who had been referred to the social services department for new permanent placement in a care home were eligible. Patients who were already residents in a care home or on a specialist stroke/rehabilitation unit were excluded. Lists were obtained twice-weekly, and the wards were visited and the patients approached. Capacity to consent to the study was assessed and those with capacity who refused were excluded, as were those without capacity whose nearest relative declined assent. In the remainder a formal test of capacity to consent to enter a care home was completed according to an algorithm (Fig. 1). The Mini-Mental State Examination (MMSE) (Reference FolsteinFolstein, 1975) was administered in most cases after the assessment of capacity. In patients with sensory deficits partial scores were normalised to a maximum of 30. Nursing, social work and medical documentation was examined for evidence of a formal or informal assessment of capacity or decision-making ability. In a random sample of 25% of cases an interview was carried out with the relevant ward doctor, social worker and key nurse to obtain a verbal assessment of the patient's capacity for the decision. In these cases notes were examined after this interview. Based on our clinical experience it was estimated that around 10% of patients would have a capacity assessment in their records, and that the study should identify a range of 0–20% with 95% confidence limits. The sample size necessary to achieve this was 35.

Fig. 1. Algorithm for assessment of capacity to enter a care home.

Ethical approval was given by the research committee of the hospital involved. Ethical approval for obtaining data from records of patients not consenting to nor being assented for the study was not sought for this study.

Results

Data were gathered from November 2004 to July 2005. As recruitment was slow from the specialist wards for older people the study was extended to include all older people referred from any non-specialist medical ward in the hospital from April 2005.

Referrals for placement of 128 patients were made during this period; 61 of these met exclusion criteria (14 already resident in a care home, 16 not on acute general medical ward, 30 not geriatric consultant (until April 2005), 1 no English language). A further 29 patients could not be assessed (4 were placed before assessment, 5 died, 8 had capacity but refused, 4 lacked capacity to enter study and assent declined, 3 relative could not be contacted, 5 other). A total of 38 participants were interviewed and documentation examined and 10 were interviewed by staff.

The sample interviewed were 58% women, with a mean age of 83 years (s.d.=8.3); 27 (71%) lived alone prior to admission. Participants were assessed at a mean of 53 days (s.d.=27) and median of 46 days after admission. The most frequent physical health problems mentioned in the records were falls (14 participants, 37.8%) and cardiovascular problems (7 participants, 18.4%); 19 participants (50%) had a recorded diagnosis of a dementia, 2 of substance misuse, 1 of a delusional disorder and 1 of affective disorder. Overall, 15 (39.5%) had no recorded mental health problems. In 3 participants the MMSE could not be completed. Of the remainder 26% scored 24 or higher, 29% had scores between 18 and 23, and 46% had scores of 17 or lower. All but 1 participant interviewed eventually entered a care home.

Discussion

This study has a number of limitations: the sample size was modest, but over half of those eligible had their documentation assessed. This study was also limited by the lack of a gold standard for capacity assessments in English law (Reference Cairns, Maddock and BuchananCairns et al, 2005), although the algorithm derived from the Law Commission report is probably as close to one as is achievable. Although feasible in research contexts, use of the MacCAT in the UK may not be appropriate because of differences in the nature of capacity as defined in different jurisdictions.

This study found a very high level of agreement between the MMSE and formal capacity assessments, and were the MMSE to be used routinely in individuals referred for care home placement its utility as a substitute for formal assessment of capacity would be a useful topic for further study. However, caution must be used when making important decisions such as care home placement so as no errors can occur.

There are other studies that have examined the relationship between the MMSE and capacity. Buckles et al (Reference Buckles, Powlishta and Palmer2003) found that MMSE scores were correlated with performance (P<0.0001) for understanding informed consent information for their non-treatment research study. Kim & Caine (Reference Kim and Caine2002) found that the MMSE significantly adds to identification of incapacity; however, the effect was modest with no cut-off point yielding both high sensitivity and high specificity. Pucci et al (Reference Pucci, Belardinelli and Borsetti2001) found a MMSE score below 18 had a positive predictive value of 95% and a negative predictive value of 63.3%. These studies looked at hypothetical research scenarios and assessments of capacity were for the decision to be involved in the research.

The main finding was a lack of documentation of capacity to give or withhold consent to admission to a care home, although this was better than we had predicted. Where there were more than one recorded assessment these were not necessarily in agreement, which may have been due to fluctuation in capacity, which this study was not designed to corroborate or refute. However, the absence of any recorded assessment in at least a third of patients is worrying, given the importance of the decision to the patients’ lives and their financial status. It may be tempting to suggest that all individuals in whom incapacity is suspected should be referred for psychiatric assessment, but that would be unreasonable (Reference Ball and MacdonaldBall & Macdonald, 2002). It is to be hoped that the implementation of the Mental Capacity Act (2005) will rectify this situation, and we plan to repeat this study to confirm this.

Declaration of interest

None.