Background and purposes: The aim of this study was to use a modified Instrumental Activities of Daily Living scale (IADL), namely the Show Chwan Activities of Daily Living (SCADL) scale, for discriminating the severity of cognitive dysfunction in Parkinson’s disease (PD).
Methods and participants: This study was conducted in three centers in Taiwan and consecutive series of participants with normal cognition (NC), mild cognitive impairment (MCI), or different stages of dementia were enrolled. The purpose of the study was to test the performance of SCADL compared with other brief screening instruments for distinguishing dementia from normal or MCI.
Results: A total of 330 individuals with PD were enrolled, including 65 NC, 94 MCI and 171 dementia patients. The receiver operator characteristic (ROC) curves analysis showed the areas under the curve (AUC) of SCADL were 0.94, 0.83, 0.95 and 0.91 for discriminating NC/MCI and dementia, very mild dementia (VMD) and Clinical Dementia Rating Scale (CDR) 1, CDR 1 and CDR 2, and CDR 2 and CDR 3, respectively, and all AUCs were higher than other screening instruments.
Conclusion: Our study showed SCADL was effective and efficient in distinguishing the different cognitive stages of PD. This rapid screening tool can be applied in general practice as well as in a community setting to decide whether further diagnostic confirmation is necessary.