Neurosurgical Study Design: Past and Future

Clinical trials are performed to determine the safety, efficacy, or effectiveness of a medical or surgical intervention. A clinical trial is, by definition, prospective in nature with a uniform treatment of a defined patient cohort. The outcomes assessment should also be uniform. Often a control group is included. At present, the number of neurosurgical clinical trials is increasing, and the study designs have become more sophisticated. Historically, the standard of neurosurgical care has evolved from the findings from many case series and retrospective comparative studies. However, in the present report, we have focused exclusively on prospective clinical trials. An urgent need exists to understand how clinical trials have been performed in the past and how they can be improved to advance our neurosurgical practice. In the present review, we have discussed the barriers, successes, and failures regarding prospective clinical trials in neurosurgery with an outlook to the future.