This study examined the ability of the Boston Qualitative Scoring System (BQSS) in comparison to the Osterrieth scoring method to separate Parkinson's Disease patients without dementia from healthy controls at the Rey-Osterrieth Complex Figure (ROCF) copy. 30 PD participants and 30 healthy participants completed ROCF copy. The performance was scored according to both methods. The results indicated that PD patients performed significantly worse on ROCF. According to ROC analyses, BQSS Copy Total score represented the most suitable index to distinguish between the two groups: a score below or equal to 16 indicates an impaired performance. Moreover, PD participants reported lower performance in the BQSS scores of Planning and Neatness. PD patients' poor performance in ROCF copy was related to executive difficulties, specifically in terms of planning and impulsivity, instead of global visuo-constructional impairments. An extensive evaluation of copy drawings allowing to disentangle between different involved cognitive domains would be suitable, specifically in those clinical conditions like PD, in which motor impairments affect drawing performance.
Keywords: Cognition; Executive function; Neurodegenerative disease; Neuropsychology; Visuo-constructional ability.