Psychological factors affecting outcome of treatment after transcutaneous electrotherapy for persistent tinnitus.

We used transcutaneous electrotherapy to treat 27 patients with persistent tinnitus. Each patient was tested with the short form of the Minnesota Multiphasic Personality Index test (MMPI) prior to the commencement of treatment. The "unimproved" group of patients (n = 15) showed higher pretreatment scores for depression (P less than 0.05), psychasthenia (P less than 0.05) and schizophrenia (P less than 0.02). Our findings indicate that patients having significantly pathological scores on at least one of these three scales will fail to benefit from treatment. These findings also show that there appear to be psychological prognostic factors that can be used to evaluate patients receiving transcutaneous electrotherapy for persistent tinnitus.