Validity and Reliability of the Persian Version of the Comprehensive Constipation Questionnaire: A Cross-Sectional Study

Chronic constipation is one of the most common complaints of patients in developed countries, which affects 2 to 28% of the world’s population and alters patients’ quality of life extensively. This study aimed to determine the validity and reliability of the Persian version of the comprehensive constipation questionnaire.

The comprehensive constipation questionnaire was translated into Persian, and its back-translation was confirmed after evaluating the content validity ratio index (CVR) based on Lawshe table (CVR≥0.62). The content validity of the questionnaire was assessed by the content validity index, followed by examining its reliability by Cronbach alpha and test-re-test reliability using the intra-class correlation coefficient (ICC). A total of 100 patients with chronic constipation completed the questionnaire.

Content validity was confirmed in the range of 0.84 to 1.00, and the Cronbach alpha values in the range of 0.90-1.00 were acceptable. In this questionnaire, was ICC in the range of 0.76-0.99 which indicates a level of good to excellent reliability of the questionnaire. Also, the results of the factor analysis were confirmed at a moderate level Kaiser Meyer Olkin test (KMO>0.6) and Bartlett test (P<0.05) by extracting a 1-factor solution.

The Persian version of the comprehensive constipation questionnaire had acceptable validity and reliability and seems to be an effective tool to evaluate patients with constipation.