ABSTRACT
Evaluation is an essential component of the rational approach to decision making. Health-care evaluation involves defining the objectives of care, monitoring health-care inputs, measuring the extent to which the expected outcomes have been achieved and assessing the extent of any unintended or harmful consequences of the intervention. As Klein has pointed out, evaluation can be seen as a technical process, where performance is measured against an agreed set of fixed goals, for example, the extent to which professionally defined ‘needs’ are being met, or as an interactive process where the goals are shifting and defined by the economic and political market place and where the emphasis may be on the extent to which consumer-defined ‘demands’ are satisfied (Klein 1982). The history of evaluation in the NHS has been characterized by tension between these two approaches. The consequent failure to resolve the problem of objectives has contributed to the difficulties inherent in measuring outcomes.
