Measuring the impact of health interventions: a review of available instruments.

Interest in the measurement of the impact of health services has been increasing for three main reasons. Policy makers and service providers wish to be reassured that they are: (i) benefitting the public for whom the service is provided; (ii) in times of economic recession and limited resources, achieving the 'best value for money'; and (iii) given the need to make economies in health expenditures, maintaining standards of the health care. Recent developments in information for the evaluation of health services have tended to emphasis the control and monitoring of expenditure in preference to the control and monitoring of quality. There is concern that this might lead to adverse consequences for patients and for the health service as a whole in that the quality of services provided might deteriorate. Health interventions are considered to be successful if they result in a beneficial change in the health of the population for whom they are provided. If the health of the population is not improved, or maintained, questions are raised about either the appropriateness of the intervention in relation to health policies which have been selected, or about the quality of the care which has been provided. Because of this, it is necessary to monitor both the outcome of a heath intervention in terms of the change in the level of health of the population, and also to measure the quality and the effectiveness of the care provided. Health services research has, over the years, developed a number of different types of measures which can be applied to health services and has suggested a number of applications for such measures in terms of the impact on the health of patients and the general population and the quality and effectiveness of health services. The first section of this paper reviews a selection of measures for both health and the effects of health interventions and discusses their applicability as management tools. The use to which such measures are put obviously depends upon the type of decisions which they are to inform, which in turn are dependent upon the organisational level at which the decision is to be made, and the policy objectives of the service to which they relate. The second part of the paper discusses factors which must be taken into account when choosing measures to monitor the impact of the health services. In examining the suitability of a management tool, a measure must be proven to provide information which is universally acceptable and which conforms to a number of scientific standards.(ABSTRACT TRUNCATED AT 400 WORDS)