Validation of the chronic venous insufficiency quality of life questionnaire in Dutch patients treated for varicose veins.

BACKGROUND

The Chronic Venous Insufficiency Quality of Life Questionnaire (CIVIQ) is a disease-specific instrument to measure the impact of chronic venous insufficiency (CVI) on patients' lives. The objective of this study is to test the psychometric properties of the CIVIQ, and to validate the use of the questionnaire translated into the Dutch language.

METHODS

A standardised questionnaire, including CIVIQ and Short Form (36) Health Survey (SF-36), was obtained before and 1 month after treatment to all new patients with varicose veins. The feasibility was tested by missing responses and response distribution. CIVIQ scores were compared to the SF-36 scores and between different levels of severity of varicose veins. The CIVIQ's reliability was assessed using Cronbach's alpha and test-retest reliability. The structure was studied using factor analysis. The scores before and after therapy were compared to assess responsiveness.

RESULTS

There was a response rate of 93.5%. None of 20 items missed < 10% of responses, but three showed ceiling effect. The CIVIQ correlated well with the physical and moderately with the mental MCS of the SF-36, suggesting a good construct validity of the CIVIQ. The median CIVIQ scores increased significantly with the severity of varicose veins. The CIVIQ showed an excellent internal consistency and an excellent test-retest reliability. The CIVIQ score decreased in 76% of patients after treatment. The results were in accordance with the Norman's rule and showed a median effect size.

CONCLUSION

This study confirms the feasibility, validity, reliability and responsiveness of the CIVIQ in patients with varicose veins. The psychometric properties of the Dutch CIVIQ were comparable to the original French version.