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.