title: Metric properties of the mini-mental Parkinson and SCOPA-COG scales for rating cognitive deterioration in Parkinson's disease.
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.
authors.affiliation: Movement Disorder and Biostatistic Units, Neurological Service, Carlos Andrade Marín Hospital, Quito, Ecuador. mserranod@gmail.com
authors.forename: Marcos
authors.initials: M
authors.lastname: Serrano-Dueñas
authors.forename: Belén
authors.initials: B
authors.lastname: Calero
authors.forename: Soledad
authors.initials: S
authors.lastname: Serrano
authors.forename: Maite
authors.initials: M
authors.lastname: Serrano
authors.forename: Paulina
authors.initials: P
authors.lastname: Coronel
mesh_terms: D000368:Aged; D003071:Cognition / Q000502:physiology*; D003072:Cognition Disorders / Q000175:diagnosis* / Q000503:physiopathology / Q000523:psychology; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000503:physiopathology* / Q000523:psychology; D011594:Psychometrics; D015203:Reproducibility of Results; D012720:Severity of Illness Index