Limitations of evidence-based medicine: the role of experience and expert opinion.
BACKGROUND: Advances in statistical science and the development of computers (a result of the digital revolution) have allowed many disciplines, including medicine, to develop a more objective analysis of data as applied to decision making. The concept of evidence-based medicine (EBM) includes that scientific study of disease and treatment efficacy will allow high-quality, cost-effective treatment. The concept of EBM is well established in medical specialties, particularly for cardiovascular disease and cancer, but less developed in the surgical specialties. Multiple factors make evidence-based surgical (EBS) studies more problematic. Entering children into prospective surgical treatment trials remains difficult for the parents and patients who are asked to allow a choice of procedures for a surgical intervention that will take just an hour or two but whose results could change the child's entire life. Comparative effectiveness research, a subset of EBM, is of special interest to surgeons, who often need to decide on an expensive new implant versus a reliable, less expensive, established one. Factors that make the scientific analysis of surgical treatment efficacy more difficult include issues as practical as surgical skill. Prescribing an antihypertensive medication or a lipid-lowering drug has little variability in its delivery. Performance of a complex surgical procedure can vary immensely, allowing a procedure to be very effective in one surgeon's hands but far less applicable by another surgeon (eg, arthroscopic vs. open shoulder surgery). Thus, large patient series with careful follow-up are required to clarify outcome differences. Scientific study of surgical treatment outcomes in childhood orthopaedic conditions remains in its infancy. Because of minimal funding available for such research, most available studies are poorly designed with an inadequate study sample size. As for the near future, neither the government nor industry sources seem to have a strong incentive to study outcomes in childhood surgical diseases that have a low prevalence. Because current research provides little evidence to guide parents and their surgeon (when a choice exists), consumers generally seek what they believe to be the best available "expert opinion." CONCLUSIONS: Properly funded, the digital revolution will allow radical advances in establishing EBS decision making. However, the same digital revolution has produced an educated populace, greatly increasing their capacity for critical analysis of available data. Currently, both sophisticated parents and their surgeons remain hesitant to accept results from poorly designed studies when deciding on surgery for their child. As a result, expert opinion remains central to surgical decision making in children's orthopaedics. Knowledgeable surgeons look forward to future quantum improvements in research quality that will allow secure EBS-based decisions for their surgical patients.