Psychometric properties of the Persian version of the Tinnitus Handicap Inventory (THI-P)

Tinnitus can have a significant effect on an individual’s quality of life, and is very difficult quantify. One of the most popular questionnaires used in this area is the Tinnitus Handicap Inventory (THI). The aim of this study was to determine the reliability and validity of a Persian translation of the Tinnitus Handicap Inventory (THI-P). This prospective clinical study was performed in the Otolaryngology Department of Guilan University of Medical Sciences, Iran. A total of 102 patients aged 23–80 years with tinnitus completed the (THI-P). The patients were instructed to complete the Beck Depression Inventory (BDI) and the State-Trait Anxiety Inventory (STAI). Audiometry was performed. Eight-five patients were asked to complete the THI-P for a second time 7–10 days after the initial interview. We assessed test–retest reliability and internal reliability of the THI-P. Validity was assessed by analyzing the THI-P of patients according to their age, tinnitus duration and psychological distress (BDI and STAI). A factor analysis was computed to verify if three subscales (functional, emotional, and catastrophic) represented three distinct variables. Test–retest correlation coefficient scores were highly significant. The THI-P and its subscales showed good internal consistency reliability (α = 0.80 to 0.96). High-to-moderate correlations were observed between THI-P and psychological distress and tinnitus symptom ratings. A confirmatory factor analysis failed to validate the three subscales of THI, and high inter-correlations found between the subscales question whether they represent three distinct factors. The results suggest that the THI-P is a reliable and valid tool which can be used in a clinical setting to quantify the impact of tinnitus on the quality of life of Iranian patients.