Validation of Spanish versions of the Pelvic Floor Distress Inventory (PFDI) and Pelvic Floor Impact Questionnaire (PFIQ): a multicenter validation randomized study

The purpose of this study is to validate Spanish versions of the Pelvic Floor Distress Inventory (PFDI) and Pelvic Floor Impact Questionnaire (PFIQ). Spanish versions were developed using back translation and validation was performed by randomizing bilingual women to complete the Spanish or English versions of the questionnaires first. Weighted kappa statistics assessed agreement for individual questions; interclass correlation coefficients (ICC) compared primary and subscale scores. Cronbach's alpha assessed internal consistency of Spanish versions. To detect a 2.7 point difference in scores with 80% power and alpha of 0.05, 44 bilingual subjects were required. Individual questions showed good to excellent agreement (kappa > 0.6) for all but eight questions on the PFIQ. ICCs of primary and subscale scores for both questionnaires showed excellent agreement. (All ICC > 0.79). All Cronbach's alpha values were excellent (> 0.84) for the primary scales of both questionnaires. Valid and reliable Spanish versions of the PFIQ and PFDI have been developed.