Benz T, Lehmann S, Elfering A, et al. - Chronic low back pain is identified as a multidimensional syndrome impacting physical activity and function, health-related quality of life and employment status. Via this study, researchers sought to determine the cross-sectional and longitudinal validity of single measurement scales in specific construct domains and to investigate how they collaborate to generate a comprehensive outcome, covering the complex construct of chronic low back pain before and after a standardized interdisciplinary pain program. In this prospective cohort study, 177 patients (mean age: 48.0 years (+/− 12.7); 59.3% female) were assessed employing the Short Form 36 (SF-36), the Multidimensional Pain Inventory (MPI), the Symptom Checklist-90-Revised (SCL-90-R), the Oswestry Disability Index (ODI), and 2 functional performance tests, the Back Performance Scale (BPS) and the 6-Minute Walking Distance (6MWD). Correlation of SF-36 Physical functioning was highest with the functional performance tests and ODI. Consistent but weaker correlations of change scores (difference of follow-up – baseline score) were observed. Two factors were identified in factor analysis: “psychosocial” and “pain & function” (totally explained variance 44.0–60.9%). Confirming previous findings, this study suggests chronic low back pain syndrome as highly multifactorial and involves many more dimensions of health and quality of life than only back-related functioning. They emphasize including the predominant psychosocial domain and a broad spectrum of measurement constructs in a comprehensive outcome measurement in order to determine the full complexity of the chronic low back syndrome. The overlapping contents and nuances within the constructs can be captured by the convergence and divergence of the scales.