Context-dependency of the REM sleep behavior disorder screening questionnaire - Clinical utility under scrutiny

Introduction

The REM Sleep Behavior Disorder (RBD) Screening Questionnaire (RBDSQ) is a widely established screening tool for detecting isolated RBD (iRBD). However, its accuracy may depend on its application context, e.g., the individuals’ awareness of their RBD status. The present work aims to describe the context-dependency and retest reliability of the RBDSQ in an iRBD cohort setting.

Methods

Ninety-four individuals with video-polysomnography confirmed iRBD answered the RBDSQ during pre-polysomnography screening (V0) and post-diagnosis (V1).

Results

The RBDSQ total score significantly differed between V0 and V1 (F(1,92) = 8.02, p = .006, η_p² = 0.019). The intraclass correlation coefficient (ICC_2,1) of the RBDSQ showed moderate reliability between consecutive timepoints (^V0-V1ICC_2,1 = 0.544). The highest Cohen's κ was reached for items 5, 6.3, 6.4, 8, and 9 across timepoint comparisons (0.409 ≤ Cohen's κ ≤ 0.660).

Conclusion

Our findings underscore the context-dependency of the RBDSQ and fluctuations in self-awareness of sleep-related behaviors, necessitating a critical appraisal of questionnaire-based RBD screening tools. Future studies should explore strategies to improve the reliability and accuracy of RBD screening tools, considering the dynamic nature of sleep-related behavior.