Abstract
Parkinson's disease (PD) is a chronic neurodegenerative disorder that causes cognitive impairment and dementia in ∼30% of patients. Objective: Compare metric qualities of Mini‐Mental Parkinson (MMP) and scales for outcomes in Parkinson's disease‐cognition (SCOPA‐COG) with respect to their relative reliability, validity and ability to predict symptoms (mobility, quality of life, social repercussions, and mood) in PD patients. Outpatients (n=123, 78 males/45 females) diagnosed with PD were included in the study. A multilevel (hierarchical) modeling analysis was performed along with tests of reliability and validity to ascertain which of the two models better predicts symptoms related to PD. Results: The MMP differed significantly between patients with Hoehn and Yahr (H&Y) stages 1, 2 or versus 4/5 (grouped together). The SCOPA‐COG showed differences only between patients in H&Y stages 2 versus 4/5. Both scales were dependent on educational background and age. The SCOPA‐COG had a higher coefficient of variation (0.303) than the MMP (0.184), indicating that it was the more discriminative of the two. Conclusions: The SCOPA‐COG has some advantages over the MMP, the most important being a greater discriminative ability. Multilevel hierarchical analysis clarified the necessity of stratifying the PD population according to educational background, years of illness, and H&Y stage when using these scales. © 2010 Movement Disorder Society