Methodology of clinical trials for tinnitus

Abstract

Keypoints: 1. There is no established methodology for clinical trials of tinnitus treatment. 2. Inter-study comparability is difficult due to insufficient characterization of investigated samples and variation of the used assessment and outcome measures. 3. Clinical trials in tinnitus should follow standards set by the guidelines of Good Clinical Practice, by the Consort statements, and should be registered in a clinical trial registry. 4. The design of the clinical trial depends on the clinical question, which should be answered by the study. 5. Placebo-controlled randomized trials represent the gold standard for testing efficacy of treatment approaches. However, in order to save resources, a stepwise approach seems reasonable, which involves pilot open trials as a first step to screen for potentially promising treatments and which is followed in case of positive outcome by randomized controlled trials. 6. Due to the heterogeneity of tinnitus, the best possible characterization of the investigated study sample, with respect to clinical or neurobiological characteristics, is highly desirable. 7. Outcome criteria for therapeutic trials have to be reliable, valid, specific, and relevant. 8. Trial design should be based on statistical estimation of sample sizes and power in order to minimize the risk of type I and type II errors. 9. To enhance inter-study comparability, international accepted standards for patient assessment and outcome measurement should be followed. 10. Standardization of clinical trial methodology will enhance clinical research in tinnitus by facilitating data comparison across trials and allowing pooled data analyses of multicenter study results in international databases. © Springer Science+Business Media, LLC 2011.