title: Testing reliability and validity of oral impacts on daily performances for Chinese-speaking elderly Singaporeans.
abstract: OBJECTIVE
  To cross-culturally adapt the oral impacts on daily performance (OIDP) and assess its reliability and validity on Chinese-speaking community dwelling elderly Singaporeans.
  
  
  BACKGROUND
  There are no previous reports of valid oral health-related quality of life instruments for elderly Singaporeans or perceived conditions associated with impacts reported in OIDP among the Singaporean elders.
  
  
  METHODS
  The OIDP was translated from English to Chinese and then back translated. The OIDP questionnaire along with questions related to overall quality of life and self-rated dental health was administered to 202 Chinese-speaking elderly Singaporeans by trained interviewers, and it was repeated after 1 month. Test-retest reliability was assessed using intraclass correlation coefficient; internal consistency was established using Cronbach's alpha, and construct validity using correlation coefficients with self-reported oral health-related and global quality of life measures. In addition, Kruskal-Wallis tests assessed differences in the OIDP score between different subjective health and global quality of life groups.
  
  
  RESULTS
  The median age of participants was 75 years. About 19% reported oral impacts and difficulty eating was the most prevalent oral impact. Internal consistency was good with a Cronbach's alpha of 0.75, and the intraclass correlation coefficient was 0.75 (0.67-0.81). OIDP was significantly correlated with all measures of self-reported oral health and global ratings of quality of life, with correlation coefficients ranging between 0.15 and 0.52. Groups with worse perceptions about their health and quality of life had significantly higher OIDP scores.
  
  
  CONCLUSIONS
  The OIDP showed successful reliability and validity for its use among Chinese-speaking older Singaporeans.
authors.affiliation: Oral Science, Faculty of Dentistry, National University of Singapore, Singapore.
authors.forename: Rahul
authors.initials: R
authors.lastname: Nair
authors.affiliation: Research Department of Epidemiology and Public Health, University College of London, London, UK.
authors.forename: Georgios
authors.initials: G
authors.lastname: Tsakos
authors.affiliation: Oral Science, Faculty of Dentistry, National University of Singapore, Singapore. rrrscr5052@gmail.com.
authors.forename: Robert
authors.initials: R
authors.lastname: Yee Ting Fai
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D044466:Asian People; D006801:Humans; D057187:Independent Living; D009909:Oral Health; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012846:Singapore; D011795:Surveys and Questionnaires / Q000592:standards*
keywords: elderly; oral function; oral health; outcome measures; quality of life