Psychometric properties of the French version of the Endometriosis Health Profile-30, a health-related quality of life instrument

Abstract

Introduction: The objectives were to evaluate the acceptability, reliability and validity of the cross-cultural adaptation of the Endometriosis Health Profile-30 instrument into French.

Methods: This cross-sectional study was conducted between July and October 2015. We created an online link (REDCap platform) with the questionnaires. An endometriosis patients association spread the link on its website and with social networks. The translation and cultural adaptation of the EHP-30 was performed according to guidelines. Psychometric evaluation included data completeness, score distributions, floor and ceiling effects, factor analysis, internal consistency, item-total correlations corrected for overlap, convergent validity and test-retest reliability.

Results: The study included 913 women with endometriosis. In our results, data completeness was excellent. No floor effects were found and one ceiling effect was observed for the 'Infertility' scale. The highest means scores were found for 'Control and powerlessness' and 'Infertility' scales. Factor analysis confirmed the structure of the original EHP-30 questionnaire. Internal consistency was good (Cronbach's α range=0.72-0.96). The correlations of similar scale scores between EHP-30 and SF-36 were all significant (Spearman correlation coefficients ranging from -0.52 to -0.75). Test-retest reliability was good (intraclass correlation coefficients range=0.51-0.98).

Conclusion: The French version of the EHP-30 is an acceptable, reliable and valid instrument for measuring health-related quality of life in women with endometriosis.

Keywords: EHP-30; Endometriosis; Quality of life; Validity.