The impact of the process of clinical research on health service outcomes.

Chapter 1 introduces the key questions and context for the work described in the supplement, on the impact of the process of clinical research on healthcare outcomes. The distinction between the influence of research activity on the outcomes for individual patients involved in clinical trials and other well-designed studies when compared to similar individuals cared for within similar healthcare institutions are considered. The evidence is reviewed and broadly the conclusion is that there is little evidence to support the hypothesis that individuals included in randomized trials do better than individuals with the same clinical characteristics in such trials within the same institution. However, the more important question of the influence of research activity on the outcomes of healthcare institutions is identified and clarified. There are less research data which address this question and it is harder to study. However, the existing data are encouraging and suggest that the hypothesis that research- intensive healthcare institutions provide improved outcomes is worthy of further study. There is a pressing need for additional high-quality, methodologically robust studies of this question.