Development And Evaluation Of Quality Of Life Instruments For Patients With Diabetes Mellitus

Object To develop and evaluate the quality of life instrument for patients with diabetes mellitus(DM).Method Based on systemetic research strategies of Quality of Life Instrument for diabetes mellitus(DM) which emphasized on combination of general module and specific module, the development work was conducted by the programmed decision and associated with Chinese culture background.Literature review,individual interviews and focus group discussions were used in instruments development.The psychometric properties of instruments were evaluated. The statistic methods used in this research including statistic descriptions,Pearson Correlation, Exploratory Factor Analysis(EFA),Hierarchical Cluster Analysis and Paired-samples t Test, Chi-square Test,One-way ANOVA,Multivariate Regression.Results(1) One 30-item general module(GM) for chronic diseases was formed.There are three domains in GM:8-item for physical functioning(PH),11-item for psychological functioning (PS) and 11-item for social functioning(SO).One 18-item specific module for diabetes mellitus were formed.Then a 30 plus 18 items instrument for patients of diabetes mellitus,shortened as QLICD-DM(V 1.0) were yielded by combination.(2) Validity:Because the item pools were nominated and several-rounds selected by persons who are strongly related with QOL study,reflecting the definition of health and QOL proposed by WHO and specific problems among patients of DM,the QLICD-DM have a considerable content validities.Most of the item scores in one domain had higher correlation with total domain score than other total domain score.The factor structures of DM were explored by using principle components analysis with varimax rotation.4 principle components which reflected content of psycho-social problems,symptoms of DM module,side effects were identified of DM and explaining 62.63%of the variance.The results built evidences of structure validity.The total scores of each domain of SF-36 were Selected as criterions,the correlation coefficients between each domain of GM and total scores of the instrument and their correlated criterions were greater than 0.5 excluded SOD and QLICD-DM.The two aspects above showed good validity of the instrument.(3) Reliability:The coefficients of internal consistency and split-half for physical functioning and psychological functioning domains of GM and DM specific module were greater than 0.7,while both of the coefficients of social functioning domain were lower than 0.7. In addition,the results of test-retest reliability indicate that between first and second time point, all domains and total scores of the instruments had no statistical significance,the correlation coefficients were greater than 0.75.The reliability of the instrument was not bad.(4) Responsiveness:The differences of each domain and total scores of the instrument between first time point and third one had statistical significance.The scale had the ability to detect clinical change due to treatment and then have good responsiveness.(5) About 15-20 minutes were spent in completing the instrument and the completed rate over 95%demonstrated that the good feasibility of the instrument.(6) Linear correlation analysis:The correlation coefficients are smaller than 0.40.The objective indicators and Quality of Life scores do not have the close degree simple straight line correlation relations.(7) Influence factor's multivariate regression analysis:economic status,indirect bilirubin, total bilirubin,high density lipoprotein cholesterol,albumin,glycerin,uric acid and hypertension history enters the different regression equation.Conclusion The QLICD-DM were valid,reliable,and sensitive,and could be used to assess quality of life among patients of DM.The objective indicators and Quality of Life scores does not have the close degree simple straight line correlation relations.The influence factors of diabetic Quality of Life mainly have:economic status,indirect bilirubin,total bilirubin,high density lipoprotein cholesterol,albumin,glycerin,uric acid and hypertension history and so on.