Lessons learned conducting a multi-center trial with a military population: The Tinnitus Retraining Therapy Trial.

Background The Tinnitus Retraining Therapy Trial (TRTT), a randomized, placebo-controlled, multi-center trial, evaluated the efficacy of tinnitus retraining therapy and its individual components, tinnitus-specific educational counseling and sound therapy versus the standard of care, in military practice to improve study participants' quality of life. The trial was conducted at six US military hospitals to take advantage of the greater prevalence of tinnitus in the military population. Methods During the trial, various challenges arose that were uniquely related to the military setting.