Validation study of REM Sleep Behavior Disorder Questionnaire – Hong Kong (RBDQ-HK) in East China

ObjectiveTo validate the REM Sleep Behavior Disorder (RBD) Questionnaire – Hong Kong (RBDQ-HK) in polysomnography (PSG)-confirmed RBD and non-RBD subjects, and to evaluate its usefulness in different clinical populations.MethodsIn total, 325 subjects (115 RBD and 210 controls) from East China were enrolled. After patients had finished the structured interview, and completed the RBDQ-HK and video-PSG test, we evaluated the reliability of RBDQ-HK (areas under the curves (AUC), the best cut-off values, factor 2 of RBDQ-HK, and overall scale) and validated the usefulness of RBDQ-HK between the Parkinson disease (PD) and obstructive sleep apnea (OSA) groups.ResultsThe best cut-off values for factor 2 of RBDQ-HK were located at 7/8 with a sensitivity of 90% and specificity of 82% (AUC = 0.911), and for RBDQ-HK overall scale were located at 17 with a sensitivity of 85% and specificity of 81% (AUC = 0.892) in all subjects. Both factor 2 and overall scale of RBDQ-HK are valid in all subjects (PD and OSA patients), with a higher accuracy given by factor 2 of RBDQ-HK.ConclusionsRBDQ-HK and its factor 2 are useful and validated RBD screening instruments, and could be used as a tool for screening RBD in patients with PD and OSA.