Cultural Adaptation and Validation of the Korean Version of the iMTA Productivity Cost Questionnaire

Abstract

This study develops the Korean version of the Institute for Medical Technology Assessment Productivity Cost Questionnaire (iPCQ) through translation/cultural adaptation and evaluation of psychometric properties. We included 110 outpatients visiting a gynecology clinic. We conducted the translation and cross-cultural adaptation of the iPCQ, including forward and back-translation, pilot test with cognitive debriefing, and finalization. We analyzed the feasibility (using average time of filling in the iPCQ and the proportion of missing values), test–retest reliability (using the intra-class correlation coefficient [ICC]), and validity (concurrent validity with the Work Productivity and Activity Impairment [WPAI] and construct validity with the 36-Item Short Form Survey [SF-36], using Spearman’s ρ). The Korean version of iPCQ showed appropriate feasibility (average filling in time was 5.0 min without missing values), and had excellent values in the domains of absenteeism, presenteeism, and unpaid work for test–retest reliability (ICC: 0.92–0.99). For concurrent validity, the Korean version of iPCQ showed moderate–high correlation for absenteeism and presenteeism with the WPAI. All domains of productivity losses measured by the Korean version of iPCQ showed negative correlation with the quality of life estimated by the SF-36. Through this study, we developed a Korean instrument that can measure and value health-related productivity losses including unpaid work as well as absenteeism and presenteeism.