Introduction to evidence-based general practice
Using Evidence-based Medicine in General practice is perhaps more challenging but rewarding than in specialist medicine. The diversity of patient problems is much greater, but this also means a greater diversity of EBM resources is available. Many GPs are wary about applying the many studies done in non-GP settings. While the average GP patient is at lower risk or has lower pre-test probabilities of serious disease, the patho-biology of the patients is not usually different. Hence some thought about the effects of risk is required to apply results from other settings (Glasziou PP, Irwig L. An Evidence-based approach to individualising treatment, British Medical Journal, 1995; 311: 356-9.). In GP settings, the harms of therapy will outweigh the benefits more often than in the lower risk general practice population.
As Gill (P. Gill, AC. Dowell, RD. Neal, et al. Evidence based general practice: a retrospective study of interventions in one training practice. BMJ 312:819-821, 1996.) have demonstrated, evidence-based general practice is applicable to the majority of patient problems but the evidence appears less often to be the highest level for the question asked. The future of evidence-based general practice will require more attention to the methods of applicability of evidence and to special research tools such as the n-of-1 (single patient) trial, which help to accommodate the diversity of patients seen in the community.
Finally, the potential EBM practitioner should note that there is no conflict between a humanistic and patient centred approach to practice and the scientific rigor of EBM. Part of acting as a source of support and information for patients is a discussion and use of the best evidence.