title: Assessing the test-retest repeatability of the Vietnamese version of the National Eye Institute 25-item Visual Function Questionnaire among bilateral cataract patients for a Vietnamese population.
abstract: OBJECTIVE
  To determine the test-retest repeatability of the National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25) for use with older Vietnamese adults with bilateral cataract.
  
  
  METHODS
  The questionnaire was translated into Vietnamese and back-translated into English by two independent translators. Patients with bilateral cataract aged 50 and older completed the questionnaire on two separate occasions, one to two weeks after first administration of the questionnaire. Test-retest repeatability was assessed using the Cronbach's α and intraclass correlation coefficients.
  
  
  RESULTS
  The average age of participants was 67 ± 8 years and most participants were female (73%). Internal consistency was acceptable with the α coefficient above 0.7 for all subscales and intraclass correlation coefficients were 0.6 or greater in all subscales.
  
  
  CONCLUSIONS
  The Vietnamese NEI VFQ-25 is reliable for use in studies assessing vision-related quality of life in older adults with bilateral cataract in Vietnam. We propose some modifications to the NEI-VFQ questions to reflect activities of older people in Vietnam.
authors.affiliation: School of Public Health, Curtin University, Perth, Western Australia, Australia; University of Medicine and Pharmacy, Ho Chi Minh City, Vietnam.
authors.forename: Kien Gia
authors.initials: KG
authors.lastname: To
authors.forename: Lynn
authors.initials: L
authors.lastname: Meuleners
authors.forename: Huei-Yang
authors.initials: HY
authors.lastname: Chen
authors.forename: Andy
authors.initials: A
authors.lastname: Lee
authors.forename: Dung Van
authors.initials: DV
authors.lastname: Do
authors.forename: Dat Van
authors.initials: DV
authors.lastname: Duong
authors.forename: Tien Duy
authors.initials: TD
authors.lastname: Phi
authors.forename: Hoang Huy
authors.initials: HH
authors.lastname: Tran
authors.forename: Nguyen Do
authors.initials: ND
authors.lastname: Nguyen
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People / Q000523:psychology; D002386:Cataract / Q000175:diagnosis* / Q000208:ethnology / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011788:Quality of Life; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D014744:Vietnam / Q000453:epidemiology; D014785:Vision, Ocular
keywords: NEI VFQ-25; Vietnamese; cataract; quality of life; repeatability