Reliability and Construct Validity of the Coping Strategy Inventory- Short Form in Hemodialysis (HD) Patients in 13 Countries in the Dialysis Outcomes and Practice Patterns Study (DOPPS).

Abstract

Background: In international studies, questionnaires are often translated into several languages without consideration of cultural and linguistic differences that may compromise the reliability and validity of survey instruments, especially those measuring psychosocial factors. The Coping Strategies Inventory-Short Form (CSI-SF) is a 16-item questionnaire, developed in English, and previously validated in US cardiac failure patients. It is scored by computing 4 scales (each with 4 items) to measure 4 different coping strategies. The aim was to assess reliability and construct validity of the CSI-SF in HD patients across 13 countries. Method(s): The CSI-SF was self-administered to HD patients across 13 countries in 9 languages in DOPPS 4 (2009-11). Cronbach's alpha was used to assess internal consistency. Exploratory and confirmatory factor analyses were used to assess the factor structure of the CSI-SF by country and language. Result(s): 6,656 HD patients completed the CSI-SF and were included in this analysis (55% male; median age=63, range: 18-96 yrs). Using the English version in 4 countries and the Swedish version, we found good internal consistency (alpha=0.63-0.77) for 3 of the 4 scales; the 4th scale was internally consistent if two items were dropped. In these countries, both types of factor analyses indicated a factor structure perfectly consistent with these same 4 scales. In the 8 other non-English versions, results were very different: internal consistency was lower for the 4 scales; no country showed an exploratory factor structure similar to that found previously, nor was the 4-factor structure confirmed with factor analysis. Conclusion(s): The CSI-SF is reliable for measuring coping in HD patients in English and Swedish versions, as tested in the DOPPS. The importance of coping for predicting outcomes in HD patients can now be described in these countries. More research is needed for measuring coping strategies in other countries and languages.