Routine outcome assessment in mental health services

Measuring and interpreting outcome is more difficult in mental health services than in some other areas of health care, for at least five reasons. First, the effect of the treatment may be to slow decline or to maintain the current level, so the score on the outcome measure itself may not improve (or may even get worse) despite best quality clinical care. Secondly, the best available evidence in the United Kingdom indicates that clinical and social variables predict no more than 30% of the variance in an individual’s quality of life (UK700 Group, 1999). Thirdly, different types of outcome are desynchronous (e.g. Drury et al. 1996), changing at different rates during an intervention. Fourthly, there may not be agreement regarding what is a positive change in outcome – the patient who has fewer episodes of mania as a result of treatment may see this as a negative outcome. Finally, three levels of mental health service can be differentiated: treatment (specific interventions),‘programme (combination of different treatment components) ; and system (all programmes for a defined target group in a given area) (Burns & Priebe, 1996). The outcome data needed to evaluate each level will be very different. The solution to these issues that has evolved in research studies has been to assess a wide range of treatment and programme-level outcomes, from multiple perspectives. For example, the programme-level PRiSM Psychosis Study evaluated two models of community care for people with psychotic diagnoses (Thornicroft et al. 1998). The outcome domains assessed by interviewing the patient were symptomatology, needs, quality of life, services being received (to allow economic analysis), social network and satisfaction with care. The outcome domains assessed by interviewing staff were global level of functioning, needs and social behaviour, and by interviewing carers were their experience of care-giving and their own symptomatology. All interviews were conducted by researchers. In general, most research and evaluation studies take place in ‘research contexts where specifically funded and trained external raters parachute into routine clinical settings in order to guarantee the validity and reliability of study measures ’ (Harrison & Eaton, 1999, p. 187).