title: Calibration and validation of the Physical Activity Barrier Scale for persons who are blind or visually impaired.
abstract: BACKGROUND
  It is critical to employ accurate measures when assessing physical activity (PA) barriers in any subpopulation, yet existing measures are not appropriate for persons with blindness or visual impairment (PBVI) due to a lack of validity or reliability evidence.
  
  
  OBJECTIVE
  To develop and calibrate a PA barrier scale for PBVI.
  
  
  METHODS
  An expert panel (n = 3) and 18 PBVI were recruited to establish content validity for a PA barriers subscale; 160 PBVI (96 females) completed the scale along with the Physical Activity Scale for Individuals with Physical Disabilities for calibration. To establish construct-related validity evidence, Confirmative factor analysis (CFA) and Rasch analysis were applied. To investigate internal consistency and reliability, Cronbach's alpha and the reliability coefficient (R) were employed, respectively.
  
  
  RESULTS
  Following CFA and Rasch analyses, five items were eliminated due to misfits; reliability coefficients were unchanged upon deletion of these items. The barriers perceived by PBVI to have the most negative impact on PA included "lack of self-discipline" (logit = 1.40) and "lack of motivation" (logit = 1.27). "Too many stairs in the exercise facility" (logit = -1.49) was perceived to have the least impact.
  
  
  CONCLUSIONS
  The newly-developed scale was found to be a valid and reliable tool for evaluating PA barriers in PBVI. To enhance promotion of health-producing levels of PA in PBVI, practitioners should consider applying this new tool as a precursor to programs aimed at improving PA participation in this group.
authors.affiliation: Department of Sport, Health, and Rehabilitation, Kookmin University, South Korea. Electronic address: mylee@kookmin.ac.kr.
authors.forename: Miyoung
authors.initials: M
authors.lastname: Lee
authors.affiliation: University of Illinois at Urbana-Champaign, USA.
authors.forename: Weimo
authors.initials: W
authors.lastname: Zhu
authors.affiliation: Roanoke College, USA.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Ackley-Holbrook
authors.affiliation: Wisconsin Center for the Blind and Visually Impaired, USA.
authors.forename: Diana G
authors.initials: DG
authors.lastname: Brower
authors.affiliation: University of Illinois at Urbana-Champaign, USA.
authors.forename: Bryan
authors.initials: B
authors.lastname: McMurray
mesh_terms: D000328:Adult; D000368:Aged; D001290:Attitude; D001766:Blindness / Q000523:psychology*; D002138:Calibration; D006233:Persons with Disabilities / Q000523:psychology; D015444:Exercise / Q000523:psychology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009042:Motivation; D011594:Psychometrics / Q000379:methods*; D015203:Reproducibility of Results; D014785:Vision, Ocular; D019987:Persons with Visual Disabilities / Q000523:psychology*; D055815:Young Adult
keywords: Assessment; Disability; Promotion of physical activity