LAUSR

The Clock Drawing Test (CDT) is among the most researched cognitive measures and is frequently used to screen for neurocognitive disorders (NCDs). No study to date has investigated the relationship between qualitative errors on the CDT and independence in instrumental activities of daily living (IADLs) or discrete cognitive abilities. Therefore, this study sought to evaluate the correlations between qualitative errors on the CDT and IADL status as well as performance in individual cognitive domains. Data were retrospectively collected from patients seen at an outpatient clinic in eastern Massachusetts, including 16 healthy controls, 22 patients with mild NCD, and 35 patients with major NCD. Analyses were performed between qualitative errors on the CDT and patients’ scores on the Lawton IADL Scale, Mattis Dementia Rating Scale-2 (DRS-2), Digit Span Forward and Backward, Trail Making Test (TMT), and the Boston Naming Test (BNT). IADL scores were moderately correlated with CDT error types. DRS-2 scores were strongly correlated commission of qualitative errors. Strong to very strong correlations were observed between TMT parts A & B scores and all qualitative error types. BNT performance was strongly correlated with conceptual deficits and spatial/planning errors. Digit Span Forward and Backward scores showed low correlations with all CDT errors. Functional status appears only moderately correlated with commission of various CDT errors; however, several cognitive measures showed high correlation with various CDT error types. These findings suggest that certain qualitative errors may be indicative of cognitive impairments warranting further workup. Clinical implications and future directions are discussed.