title: Assessment of tinnitus-related impairments and disabilities using the German THI-12: sensitivity and stability of the scale over time.
abstract: OBJECTIVE
  To evaluate the reliability, dimensionality, predictive validity, construct validity, and sensitivity to change of the THI-12 total and sub-scales as diagnostic aids to describe and quantify tinnitus-evoked reactions and evaluate treatment efficacy.
  
  
  METHODS
  Explorative analysis of the German tinnitus handicap inventory (THI-12) to assess potential sensitivity to tinnitus therapy in placebo-controlled randomized studies. Correlation analysis, including Cronbach's coefficient α and explorative common factor analysis (EFA), was conducted within and between assessments to demonstrate the construct validity, dimensionality, and factorial structure of the THI-12.
  
  
  METHODS
  N = 618 patients suffering from subjective tinnitus who were to be screened to participate in a randomized, placebo-controlled, 16-week, longitudinal study.
  
  
  RESULTS
  The THI-12 can reliably diagnose tinnitus-related impairments and disabilities and assess changes over time. The test-retest coefficient for neighboured visits was r > 0.69, the internal consistency of the THI-12 total score was α ≤ 0.79 and α ≤ 0.89 at subsequent visits. Predictability of THI-12 total score and overall variance increased with successive measurements. The three-factorial structure allowed for evaluation of factors that affect aspects of patients' health-related quality of life.
  
  
  CONCLUSIONS
  The THI-12, with its three-factorial structure, is a simple, reliable, and valid instrument for the diagnosis and assessment of tinnitus and associated impairment over time.
authors.affiliation: Merz Pharmaceuticals GmbH Global R&D, Eckenheimer Landstrasse 100, Frankfurt am Main, Germany. roman.goertelmeyer@merz.de
authors.forename: Roman
authors.initials: R
authors.lastname: Görtelmeyer
authors.forename: Jürgen
authors.initials: J
authors.lastname: Schmidt
authors.forename: Markus
authors.initials: M
authors.lastname: Suckfüll
authors.forename: Pawel
authors.initials: P
authors.lastname: Jastreboff
authors.forename: Alexander
authors.initials: A
authors.lastname: Gebauer
authors.forename: Hagen
authors.initials: H
authors.lastname: Krüger
authors.forename: Werner
authors.initials: W
authors.lastname: Wittmann
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001306:Auditory Pathways / Q000503:physiopathology*; D017281:Cost of Illness; D004185:Disability Evaluation; D005163:Factor Analysis, Statistical; D005260:Female; D005858:Germany; D006801:Humans; D007802:Language; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011788:Quality of Life; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013997:Time Factors; D014012:Tinnitus / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology / Q000628:therapy; D016896:Treatment Outcome; D055815:Young Adult