Cross-cultural adaptation and reliability of the German version of the back pain attitudes questionnaire (Back-PAQ-G)

Background Low back pain (LBP) affects at least 80% of individuals during their lifetime and incurs significant healthcare costs, with around 90% being classified as non-specific. Psychosocial factors, including kinesiophobia and pain catastrophizing, are critical in the risk of LBP chronicity. While various validated questionnaires assess these factors, a reliable German version of the Back Pain Attitudes Questionnaire (Back-PAQ) was previously lacking. This study aimed to translate and cross-culturally adapt the Back-PAQ into German (Back-PAQ-G) and estimate Cronbach’s alpha and evaluate test–retest reliability among individuals with and without LBP as well as healthcare professionals. Methods This cross-sectional study included translation, cross-cultural adaptation, and reliability assessment of the Back-PAQ into German according to established guidelines. A total of 112 participants were recruited: 30 reported current LBP, 67 previous LBP but no current LBP, and 15 had never experienced LBP; 74 participants were healthcare professionals. Baseline and follow-up assessments were conducted online with a 7–14-day interval. Statistical analyses included Cronbach’s alpha, Intraclass Correlation Coefficient (ICC), and Limits of Agreement for the Back-PAQ-G (34 items), Back-PAQ-G-20 (20 items), and Back-PAQ-G-10 (10 items). Results The translation and cross-cultural adaptation process resulted in a finalized German version of the Back-PAQ suitable for the DACH region following resolution of discrepancies through collaboration with the original author and an expert committee. Cronbach’s alpha was 0.94 for the Back-PAQ-G, 0.91 for the Back-PAQ-G-20, and 0.83 for the Back-PAQ-G-10. Test–retest reliability was good to excellent, with ICC values of 0.95, 0.93, and 0.90, respectively. Conclusions Cronbach’s alpha ranged from 0.83 to 0.94 across the three versions and is reported descriptively, while test–retest reliability was good to excellent in this sample. Interpretation of Cronbach’s alpha should additionally consider evidence on structural validity. Trial registration ClinicalTrials.gov (NCT05960760). Registered 17 July 2023; prospectively registered. Project-ID 2023-00952 of the Cantonal Ethics Committee Zürich & Basel