Cross-cultural adaptation, validity and reproducibility of the Back Beliefs Questionnaire among older Brazilians with acute low back pain. A cross-sectional study.

Background: Low back pain (LBP) has emerging as an epidemic, multifactorial and multidimensional condition in older age. Assessment of attitudes and beliefs of patients with back pain is necessary for understanding the impact of psychosocial factors on pain perception and management.

Objectives: To cross-culturally adapt and examine the validity and reproducibility (intra and interrater reliability and agreement) of the Back Beliefs Questionnaire (BBQ) in older Brazilians with acute LBP.

Design And Setting: Cross-sectional methodological report conducted at the Department of Physical Therapy of the Universidade Federal de Minas Gerais, Belo Horizonte, Brazil.

Methods: The present study was conducted for translating, adapting, and examining the psychometric properties of a questionnaire. Participants aged ≥ 60 years experiencing an acute episode of LBP were recruited. Coefficients of internal consistency, reliability and agreement were obtained using Cronbach's α, intraclass correlations, and standard error of measurement and the smallest detectable change, respectively.

Results: Twenty-six participants aged between 60-84 years and reporting a mean of 9.8 (4.3) years of schooling completed the study. The Brazilian Portuguese-language version of the BBQ (BBQ-Brazil) was proposed and presented with adequate conceptual, semantic, operational, and measurement equivalence from the original version. Intra and interrater evaluations showed moderate (0.74) and excellent (0.91) intraclass correlation coefficients, respectively, with small standard error of measurement for both evaluations. Internal consistency was considered adequate (0.70).

Conclusion: BBQ-Brazil had consistent measurements of validity and reproducibility, and proved to be a valuable tool in clinical practice for addressing attitudes and beliefs of older patients with acute LBP.