The Research Of Quality Of Life In An Urban Elderly Population Using The SF-36 Health Survey

IntroductionRapid economic developments in China have resulted in an increase in life expectancy and aging of the population. The proportion of the population aged 60 or over has doubled. The quality of life in an elderly population may directly show the level of medical care in this country. So more and more people pay attention to the quality of life among old people. The SF-36 Health Survey was developed by Ware et al. in the United States on the basis of the MOS in 1990, which is a multi-purpose, short-form health survey. In china, the SF-36 Health Survey was translated and tested in small population in 1996. But it isn't reported that whether the SF-36 is suitable for use with old people. Therefore, it is necessary for us to study an objective and scientific method to assess the quality of life and to analyze impact factors among old people. We investigated health status of old people in communities using the Chinese SF-36 Health Survey translated by Zhongshan Medical University, assessed the outcomes , and analyzed the impact factors on Physical and Mental Component Summary. It provides some evidences for further research and applications.Data CollectionThe data for the current study came from 7 communities. The subjects of survey were people aged over 60 and had worked for 5 years or over before they retired in Shenyang . Data was collected from May to October, 2000. The survey was conducted through a face- to-face interview. Such sociodemographic characteristics as age, sex, education, marital status, occupation, economic income, etc. were considered and the SF-36 Health Survey was used in this survey. Investigators recorded all answers, and took the questionnaires to Study Center. Data was input into IBM 586, and analyzed by SAS 6. 12.Analytic Methods(l)The assessments of the SF-36It was hypothesized that it was less likely for people to be able to achieve higher than lower levels of function or to endorse positive than negative health states. Item internal consistency is tested by examining the correlation between an item and the scale score computed from all otheritems in that scale. It has been considered substantial andsatisfactory if an item correlation is 0. 40 or more with itshypothesized scale. Item discriminant validity is supportedif the correlation between an item and its hypothesized scale is significantly higher than the correlations betweenthat item and all other scales. When the correlation between item and its hypothesized scale was two standard errors higher than the same item's correlation with all other scales, the percent of scaling success was considered 100%. The reliability of each scale was assessed by Cronbach's a coefficient. It is a measure of how the items within a scale correlates with each other, and therefore indicates the extent of the scale's correlations with themselves. Coefficient a should equal to or over the interscale correlations. Previous factor analysis in the United States and Western European countries had confirmed the construct validity of the SF-36 in relation to its hypothesized two principal components of health (physical and mental health). To test whether our results fitted the hypothesized physical and mental structure of the original SF-36, two principal components were extracted from the correlation among the eight scales of the sample and rotated to orthogonal simple structure using SAS6. 12.(2)The analysis of the impact factors on the qualityof life among old peopleUsing multi-variable Logistic Stepwise Regression, the study was designed to explore to the impact factors onphysical and mental health. The independent variablesincluded age, sex, education, occupation, etc. Thedependent variables were the scores of physical and mental principal components.Results(l)The concepts and construct of the SF-36The clustering and ordering of the item means of our subjects were the same as that hypothesized, except for items PF2, RP3 and GH4. The correlation between an item and its...