Sleep Disability Questionnaire in Chronic Low Back Pain: A Study Protocol for Development, Validation, and...

Chronic low back pain (CLBP) is a prevalent musculoskeletal disorder, affecting up to 80% of people in their lifetime. Approximately 70% of CLBP patients report significant sleep disruptions, indicating an important but under-recognized element of their condition. Existing evaluation tools rarely account for this population's unique issues in assessing chronic pain and sleep problems.

This study involves two parts. We will design and evaluate the CLBP-specific Sleep Disability Questionnaire (SDQ) in Phase 1. Through expert discussions, patient interviews, and extensive literature analysis, domain identification is achieved. The Delphi technique will ensure content validity, followed by pilot testing to assess questionnaire usefulness and efficacy. Exploratory factor analysis will evaluate construct validity. Phase 2 will assess SDQ reliability and psychometric features, including internal consistency and inter/intra-rater reliability, in 51 CLBP patients with sleep disorder.

Psychometric examination will establish content validity using kappa statistics, I-CVI, and S-CVI. Kolmogorov-Smirnov and Shapiro-Wilk tests will determine normality. Regression, Cronbach's alpha, Pearson or Spearman correlations, Bland-Altman plots, and intraclass correlation coefficients are reliability analyses.

This work develops and validates a novel, robust SDQ for CLBP patients. The SDQ should help physicians and researchers diagnose and manage sleep disorders in this patient group, improving clinical outcomes and quality of life.