Measurement invariance of the kidney disease and quality of life instrument (KDQOL-SF) across Veterans and non-Veterans

Health and Quality of Life Outcomes

Research

Karen L Saban¹  Kevin T Stroupe²  Denise M Hynes³  Fred B Bryant⁴  Domenic J Reda⁵ 

[1] Center for Management of Chronic Complex Care, Edward Hines Jr. VA Hospital, Hines, IL, USA;Loyola University Chicago, Marcella Niehoff School of Nursing, Maywood, IL, USA;Center for Management of Chronic Complex Care, Edward Hines Jr. VA Hospital, Hines, IL, USA;Veterans Affairs Information Resource Center, Hines, IL, USA;Loyola University Stritch School of Medicine, Maywood, IL, USA;Center for Management of Chronic Complex Care, Edward Hines Jr. VA Hospital, Hines, IL, USA;Veterans Affairs Information Resource Center, Hines, IL, USA;University of Illinois at Chicago, College of Medicine, Chicago, IL, USA;Loyola University Chicago, Department of Psychology, Chicago, IL, USA;Veterans Affairs Cooperative Studies Program Coordinating Center, Hines, IL, USA;

关键词: Chronic Kidney Disease;    Measurement Invariance;    DOPPs Sample;    Confirmatory Factor Analysis Model;    Configural Invariance;   

DOI  :  10.1186/1477-7525-8-120

 received in 2010-03-12, accepted in 2010-10-25,  发布年份 2010

来源: Springer

【 摘 要 】

BackgroundStudies have demonstrated that perceived health-related quality of life (HRQOL) of patients receiving hemodialysis is significantly impaired. Since HRQOL outcome data are often used to compare groups to determine health care effectiveness it is imperative that measures of HRQOL are valid. However, valid HRQOL comparisons between groups can only be made if instrument invariance is demonstrated. The Kidney Disease Quality of Life-Short Form (KDQOL-SF) is a widely used HRQOL measure for patients with chronic kidney disease (CKD) however, it has not been validated in the Veteran population. Therefore, the purpose of this study was to examine the measurement invariance of the KDQOL-SF across Veterans and non-Veterans with CKD.MethodsData for this study were from two large prospective observational studies of patients receiving hemodialysis: 1) Veteran End-Stage Renal Disease Study (VETERAN) (N = 314) and 2) Dialysis Outcomes and Practice Patterns Study (DOPPS) (N = 3,300). Health-related quality of life was measured with the KDQOL-SF, which consists of the SF-36 and the Kidney Disease Component Summary (KDCS). Single-group confirmatory factor analysis was used to evaluate the goodness-of-fit of the hypothesized measurement model for responses to the subscales of the KDCS and SF-36 instruments when analyzed together; and given acceptable goodness-of-fit in each group, multigroup CFA was used to compare the structure of this factor model in the two samples. Pattern of factor loadings (configural invariance), the magnitude of factor loadings (metric invariance), and the magnitude of item intercepts (scalar invariance) were assessed as well as the degree to which factors have the same variances, covariances, and means across groups (structural invariance).ResultsCFA demonstrated that the hypothesized two-factor model (KDCS and SF-36) fit the data of both the Veteran and DOPPS samples well, supporting configural invariance. Multigroup CFA results concerning metric and scalar invariance suggested partial strict invariance for the SF-36, but only weak invariance for the KDCS. Structural invariance was not supported.ConclusionsResults suggest that Veterans may interpret the KDQOL-SF differently than non-Veterans. Further evaluation of measurement invariance of the KDQOL-SF between Veterans and non-Veterans is needed using large, randomly selected samples before comparisons between these two groups using the KDQOL-SF can be done reliably.

【 授权许可】

CC BY   
© Saban et al; licensee BioMed Central Ltd. 2010