Translation, Validity, and Reliability of Singing Voice Handicap Index in Persian Traditional Singers: A New Revised Version

Background: The singing voice handicap index (SVHI) was developed to assess voice-related handicaps in singers. Objectives: purpose of this study evaluate the validity and reliability a Persian translation SVHI (P-SVHI) for traditional Methods: A cross-sectional performed translate validate P-SVHI using "forward-backward" procedure. questionnaire administered 275 singers (168 with normal 107 dysphonia) ranging from 16 83 years. Content, construct, discriminant, convergent, face validity, test-retest reliability, internal consistency, floor ceiling effects were assessed. Results: 36-item SVHI, translated original English by two translators, completed 21 After approved, construct assessment factor analysis identified four factors exclusion seven items. mean score 29-item on 0 - 100 scale 16.9 healthy subjects 40.9 dysphonic subjects. Discriminant confirmed that scores significantly different between singers, an independent sample t-test (P < 0.001). Convergent proven strong correlations Iowa Patient’s Voice Index (IPVI1, IPVI2, "IPVI effort" r = 0.58, 0.69, 0.42, respectively, P Internal consistency also excellent (Cronbach α 0.95, average inter-item correlation 0.40, intra-class coefficients two-way random model absolute agreement, ICCtwo-way random, agreement 0.69 0.95). No or observed. Conclusions: revised is valid reliable tool differentiating