Cross-cultural adaptation and validation to Brazilian Portuguese of two measuring adherence instruments for patients with type 1 diabetes

Abstract

Background: The purpose of this study was to carry out a cross-cultural adaptation to Brazilian Portuguese, validation, and comparison of two questionnaires to measure adherence in patients with type 1 diabetes. There are no validated instruments to measure treatment adherence in Brazilian patients with type 1 diabetes. Methods: Type 1 diabetes outpatients of a tertiary hospital in Southern Brazil were recruited to examine psychometric properties of the Diabetes Self-Management Profile (DSMP) and Self-Care Inventory-revised (SCI-R) adapted to Brazilian Portuguese. Analyses assessed the reliability and validity according to its associations with glycated hemoglobin (A1C). Seventy-five patients [age: 34.9± 13.7 years; A1C: 9.2±2% (75 mmol/mol); diabetes duration: 18.1±11.8 years] were evaluated. Results: The translated versions of the instruments showed adequate internal consistency (DSMP Cronbach's α =0.76; SCI-R Cronbach's α =0.71). A positive correlation was found between all the items and total scores, except for item 12 in DSMP and item 13 in SCI-R, and for this reason, these items were excluded from the translated versions. In predictive validity analysis, A1C correlated significantly with the DSMP total (r=-0.46) and with the SCI-R total (r=-0.44). Conclusions: The Brazilian Portuguese versions of DSMP and SCI-R yielded a reliable and valid tool to measure adherence treatment for patients with type 1 diabetes, with a significant correlation between total scores and A1C.