Validation of the Chinese Non-Motor Symptoms Scale for Parkinson's disease: Results from a Chinese pilot study

ObjectivesTo evaluate a Chinese version of the Non-Motor Symptoms Scale (NMSS) in Parkinson's disease (PD) as an instrument for measuring non-motor symptoms (NMSs) in Chinese patients with Parkinson's disease.MethodsWe conducted a psychometric analysis of the Chinese version of NMSS using a cross-sectional study of 126 patients with PD. The battery also included the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS), the Mini-Mental State Examination (MMSE), the Geriatric Depression Scale (GDS), and the Hamilton Anxiety Scale (HAMA), and was conducted by neurologists.ResultsThere were significant correlations between the NMSS and PSQI scores (rS = 0.63, P < 0.001), as well as the NMSS and ESS scores (rS = 0.38, P < 0.001). Furthermore, significant positive correlations between NMSS and GDS, NMSS and HAMA, and NMSS and disease duration were also observed. Importantly, the sleep/fatigue index of the NMSS significantly correlated with the PSQI and ESS findings, the mood/cognition index of the NMSS significantly correlated with the GDS and HAMA findings, and the attention/memory index of the NMSS significantly correlated with the MMSE findings.ConclusionThe Chinese version of the NMSS can be considered a comprehensive, useful measure for NMS evaluation in Chinese PD patients.