Introduction

Evaluative research in community psychiatry is one of the most difficult areas of psychiatric research. This is due to: (1) multiple conditions of care and complex measures of intervention; (2) difficulties in finding appropriate criteria and indicators of outcome (especially in assessing quality of life); (3) difficulties in measuring and controlling for relevant intervening variables; and (4) different methods and practices of data collection. As a result, it is hard to ensure both internal and external validity of the results obtained, that is, to isolate the reasons for observed changes and also to apply the results to other populations, services or community care systems. Indeed, many reviews and attempts at a meta-evaluation of studies on the effectiveness of community care (Renshaw et al.,1988; Hafner & an der Heiden, 1989) have been faced with the following problems: the patient groups studied differed in their profiles of needs for care, the underlying social and institutional conditions of the programmes and services were hardly comparable and intervening variables, such as severity of illness and the patients’ skills levels, were not taken sufficiently into account.

An additional hindrance to transnational comparative studies is the lack of comparable national databases or health information systems providing background information for a given structure of mental health care. In addition, there are differences in the organisation of health care, social and welfare systems as well as in the level of implementation of community care. As a consequence, the WHO Regional Office for Europe in its transnational comparative 10-year assessments of mental health care in the European member states included only a few crude indicators of community psychiatric care, such as number of psychiatric units in general hospitals, bed capacity and number of outpatient and day-care units (May, 1976; Freeman et al. 1985). Such an approach naturally harbours fewer errors, but also narrows the range of relevant results.

The present chapter deals with some core questions of evaluative research in psychiatry. In the first part the objectives of psychiatric care and treatment will be discussed. Rather than providing a list of operational criteria for assessing effectiveness in the evaluation of outcome, the chapter focuses on the objectives explicitly determined or merely implied by the changed assumptions, principles and value judgements in the field of community care.