The University of California San Diego Performance‐Based Skills Assessment is a valid measure of functional abilities related to cognition rather than motor symptoms in Parkinson disease (PD), according to a recent study. Furthermore, it reliably distinguishes demented from non-demented participants. 100 PD participants, ranging from normal cognition to dementia, completed the Assessment, a performance‐based measure of cognitively demanding activities of daily living, as well as a neuropsychological battery and motor examination. Cognitive classification was determined by consensus conference, blinded to Assessment scores. Researchers found:
- The Assessment demonstrated strong internal consistency (Cronbach's α = 0.82) and test‐retest reliability (r = 0.89) and correlated strongly with global cognition (Mattis Dementia Rating Scale: r = 0.80).
- Assessment regression models indicated greater contribution from cognitive explanatory variables (marginal partial: R2 = 0.33) than motor variables (marginal partial: R2 = 0.05), controlling for age, education, disease duration, and L‐dopa equivalent dose.
- Additionally, the Assessment exhibited strong discriminant validity for dementia (area under the curve = 0.91).
Holden SK, Medina LD, Hoyt B, et al. Validation of a performance‐based assessment of cognitive functional ability in Parkinson's disease. [Published online ahead of print October 10, 2018]. Mov Disord. doi:10.1002/mds.27487.