Tinnitus: the complexity of standardization.

Tinnitus is a heterogeneous disorder that causes significant impairment in many patients. Treatment is elusive and there is a need for more comprehensive guidelines for diagnosis and management of tinnitus. However, different standardization approaches should be differentiated according to their specific purpose. Standardization of assessment methods and outcome measurements are useful for the performance of clinical trials, for comparison of results across centers, for clinic audits, and for epidemiological studies. In contrast, clinical guidelines are the best approach for the standardization of the clinical management of tinnitus patients. In the development of these clinical guidelines, the heterogeneity of tinnitus should be considered. Tinnitus can be a symptom of a severe underlying disease. Also, there are specific subforms of tinnitus for which curative treatment options are available. Therefore, medical diagnosis is necessarily the first step in tinnitus management. Treatment guidelines should not be restricted to recommendations that are supported by high-level evidence. They should also contain treatment recommendations that have shown clinically highly relevant effects in case series of specific tinnitus subgroups.