title: Validity and reliability of the modified Chinese version of the Older People's Quality of Life Questionnaire (OPQOL) in older people living alone in China.
abstract: OBJECTIVE
  This study aimed to test the validity and reliability of a modified Chinese version of the OPQOL among older people living alone in China.
  
  
  BACKGROUND
  China has an ageing population with an increasing number of older people living alone who may have a poorer quality of life (QoL) in the light of the traditional culture of collectivism and filial piety. An appropriate instrument is important to assess their QoL. The Older People's Quality of Life Questionnaire (OPQOL) was developed directly from the views of older people and has been validated in England. There has been no psychometric evaluation of the scale in China.
  
  
  METHODS
  The OPQOL was translated and modified prior to being administered to a stratified random cluster sample of 521 older people living alone. Validity was assessed through convergent validity, discriminant validity and construct validity. Reliability was assessed through internal consistency and test-retest reliability.
  
  
  RESULTS
  Exploratory factor analysis indicated eight factors accounting for 63.77% of the variance. The convergent validity was supported by moderate correlations with functional ability, social support and loneliness with Spearman's rho of -0.50, 0.49 and -0.53, respectively. The discriminant validity was confirmed by differentiating QoL scores between the depressed and non-depressed groups. The Cronbach's α coefficient was 0.90 for the total scale and over 0.70 for most of its dimensions. The 2-week test-retest reliability ranged from 0.53 to 0.87.
  
  
  CONCLUSIONS
  The modified Chinese version of the Older People's Quality of Life has acceptable validity and reliability as a useful instrument to measure the QoL of older people living alone in China.
authors.affiliation: Fudan University, School of Nursing, Shanghai, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.forename: Allan
authors.initials: A
authors.lastname: Hicks
authors.forename: Alison E
authors.initials: AE
authors.lastname: While
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002681:China; D003863:Depression / Q000523:psychology; D005260:Female; D006801:Humans; D008132:Loneliness / Q000523:psychology; D008297:Male; D008875:Middle Aged; D011594:Psychometrics; D011788:Quality of Life; D015203:Reproducibility of Results; D012944:Social Support; D011795:Surveys and Questionnaires; D014177:Translations
keywords: China; Older People's Quality of Life Questionnaire; older people; quality of life; reliability; validity