Objective: To review the available evidence in order to identify effective interventions which health services alone or in collaboration with other agencies could use to reduce inequalities in health.
Methods: A search of the literature was undertaken using a number of databases including Medline (from 1990), Applied Social Science Index and Abstracts (1987-1994), and the System for Information on Grey Literature in Europe (1984-1994), on a large range of key words. Studies were included if they assessed interventions designed to reduce inequalities in health or improve the health of a population group relevant to the review, and could be carried out by a health service alone or in collaboration with other agencies. Only studies evaluating interventions using an experimental design were included. Papers in any language were considered. In addition, systematic reviews of the research on the effectiveness of health promotion and the treatment of conditions where there are significant health inequalities were identified in order to illustrate the potential for reducing inequalities in health.
Results: 94 studies were identified which satisfied all the inclusion criteria and 21 reviews were included. A number of interventions have been shown to improve the health of groups who are disadvantaged by socio-economic class, ethnicity or age and, if properly targeted, could be expected to reduce health inequalities. If a health intervention is being used, there should be evidence that it has an impact on health status. Attention should then be given to the way in which the intervention is delivered and the characteristics of a programme to promote implementation. Characteristics of successful interventions specifically aimed at reducing health differentials include: systematic and intensive approaches to delivering effective health care; improvement in access and prompts to encourage the use of services; strategies employing a combination of interventions and those involving a multi-disciplinary approach; ensuring interventions address the expressed or identified needs of the target population; and the involvement of peers in the delivery of interventions. However, these characteristics alone are not sufficient for success, nor are they universally necessary.
Conclusions: Although it is likely that the most significant contributions to reducing health inequalities will be in improving economic and social conditions and the physical environment, there are interventions which health services, either alone or in collaboration with other agencies, can use to reduce inequalities in health.