Evaluation of 5536 patients treated in an integrative outpatient tinnitus treatment center–immediate effects and a modeling approach for sustainability

BACKGROUND Tinnitus is an increasingly serious problem for health care systems. According to epidemiological data, 7-14 % of outpatients have asked their physician about tinnitus and management strategies. Integrative outpatient treatments are currently regarded as promising therapeutic approaches for managing tinnitus. In this article we report on the treatment success of an outpatient tinnitus treatment center in Germany. METHODS This cohort study included pre-post data of 5536 outpatients which were treated between 2003 and 2010 in the tinnitus-therapy center, Krefeld-Düsseldorf (TTZ). The intervention consisted of psychological immunization training as well as an auditory stimulation therapy component. The main outcome parameter was the score of the Tinnitus Questionnaire (TQ) which was assessed before and after a 9 days treatment and (in a small subsample) at a 6 months follow-up. Missing data were multiply imputed. Pre-post effect sizes were calculated and adjusted for regression to the mean (RTM). RESULTS RTM-adjusted treatment effects at the end of treatment were estimated as -18.6 (CI: -18.9 to 18.2, p < 0.001) score points which corresponds to a standardized effect of d = -1.03 (CI: -1.05 to -1.01). These effects can be corroborated in various subgroups and all subscales of the TQ (d ranging from -0.31 to -0.97). CONCLUSION The study suggests the effectiveness of this outpatient tinnitus therapy concept. Multiple imputations techniques and RTM analysis were helpful in carving out true treatment effects.