title: The Persian version of the Berg Balance Scale: inter and intra-rater reliability and construct validity in elderly adults.
abstract: OBJECTIVE
  As a well-known measure for quantifying functional mobility in elderly persons, Berg Balance Scale (BBS) was used in the present study to evaluate its psychometric properties among a sample of 106 elderly individuals speaking Persian language.
  
  
  METHODS
  After forward-backward translation process, videotapes were recorded from all participants while performing 14 tasks of the BBS. The volunteers were also asked to perform the Timed Up and Go (TUG) test at the same session. To determine inter and intra-rater reliability, the videotapes were viewed by two experienced therapists while one of the raters assessed the videotaped performance of the subjects on a second occasion.
  
  
  RESULTS
  Intraclass correlation coefficients (95% confidence interval) of 0.93 (0.87 0.96) and 0.95 (0.92 0.97) were obtained for inter and intra-rater reliability, respectively. Cronbach's alpha was 0.62 which is marginally lower than the cut-off point of 0.70. Furthermore, there were no ceiling and floor effects for the Persian version. In terms of construct validity, the BBS had a negative and strong correlation with the TUG (r = -0.74, p < 0.001).
  
  
  CONCLUSIONS
  Acceptable levels of intra and inter-rater reliability with a moderate internal consistency and high validity were demonstrated for the Persian version of BBS.
authors.affiliation: Department of Physical Therapy, University of Social Welfare and Rehabilitation Sciences, Tehran, Iran.
authors.forename: Mahyar
authors.initials: M
authors.lastname: Salavati
authors.forename: Hossein
authors.initials: H
authors.lastname: Negahban
authors.forename: Masood
authors.initials: M
authors.lastname: Mazaheri
authors.forename: Manijeh
authors.initials: M
authors.lastname: Soleimanifar
authors.forename: Mohammad
authors.initials: M
authors.lastname: Hadadi
authors.forename: Leyla
authors.initials: L
authors.lastname: Sefiddashti
authors.forename: Maryam Hassan
authors.initials: MH
authors.lastname: Zahraee
authors.forename: Keyvan
authors.initials: K
authors.lastname: Davatgaran
authors.forename: Awat
authors.initials: A
authors.lastname: Feizi
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016001:Confidence Intervals; D005260:Female; D015577:Geriatric Assessment / Q000379:methods*; D006801:Humans; D007492:Iran; D007802:Language; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D004856:Postural Balance; D011594:Psychometrics; D015203:Reproducibility of Results; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014175:Translating; D014743:Videotape Recording