STRUCTURAL VALIDATION OF THE CHRONIC VENOUS INSUFFICIENCY QUALITY OF LIFE QUESTIONNAIRE-14 (CIVIQ-14) - A CONFIRMATORY FACTOR ANALYSIS
Author(s)
Le Moine JG*;Katumba KR, Launois R Rees France, Paris, France
Presentation Documents
OBJECTIVES: The aim of this study was to confirm the factorial structure of the short version of the CIVIQ questionnaire using Vein Consult Program (VCP) results.
METHODS: The VCP was an international study aiming to evaluate the impact of chronic venous disease (CVD) on cost and quality of life. The factorial structure of CIVIQ-14 was evaluated using two methods: confirmatory factor analysis (CFA) and multitrait/multi-items matrix. CFA was performed based on the 3-dimensional structure of CIVIQ-14 established in a previous study. 6 indices from CFA were used to assess stability: Chi², Root Mean Square Approximation (RMSEA), Adjusted Goodness-of-Fit Index (AGFI), Standardized Root Mean square Residual (SRMR), Normed-Fit Index (NFI) and Comparative-Fit Index (CFI). In addition, VCP results were also used to evaluate the psychometric properties of the questionnaire. Prior to data analysis, missing data were replaced using multiple imputation and a bootstrap was conduct to take the country-effect into account. RESULTS: 47149 questionnaires from 17 countries were available in the VCP, of which 1438 were excluded for more than 50% missing values. Results from the CFA showed an acceptable adjustment of the CVIQ-14’s 3-dimensional structure to VCP data. Within absolute-fit indices, both AGFI and SRMR proved the model to be relevant (AGFI=0.905; SRMR=0.034) while RMSEA was slightly over threshold (RMSEA=0.079; threshold=0.07). Relative-fit indices were consistent with absolute indices, with NFI=0.95 and CFI=0.95. Multitrait/mutli-items analysis agreed with CFA, showing all items to be more correlated to their dimensions score, with correlation coefficient superior to 0.4. Evaluating psychometric properties of the scale, Cronbach’s alpha proved internal consistency (α>0.8 in all dimension). CONCLUSIONS: Confirmatory factor analysis on VCP data supported the stability of the CIVIQ-14 questionnaire factorial structure. An attempt has been made to evaluate the psychometric properties of the questionnaire, but, due to VCP’s transversal design, the full process hasn’t been achieved.
Conference/Value in Health Info
2013-11, ISPOR Europe 2013, The Convention Centre Dublin
Value in Health, Vol. 16, No. 7 (November 2013)
Code
PRM132
Topic
Methodological & Statistical Research
Topic Subcategory
PRO & Related Methods
Disease
Systemic Disorders/Conditions