Factor analysis of the CORE measure of psychomotor disturbance in psychotic depression: Findings from the STOP-PD II study. (August 2022)

• Record Type: Journal Article
• Authors: Bingham, Kathleen S.; Neufeld, Nicholas H.; Alexopoulos, George S.; Marino, Patricia; Mulsant, Benoit H.; Rothschild, Anthony J.; Voineskos, Aristotle N.; Whyte, Ellen M.; Meyers, Barnett S.; Flint, Alastair J.
• Is Part Of: Psychiatry research. Volume 314(2022)
• Publication Date: 2022-08
• Subjects: Psychotic depression -- Psychomotor disturbance -- CORE instrument; Psychiatry -- Periodicals; Psychiatry -- periodicals; Psychiatrie -- Périodiques; 616.89
• DOI: 10.1016/j.psychres.2022.114648
• Languages: English
• ISSNs: 0165-1781

Abstract

Highlights: The CORE is a comprehensive measure of psychomotor disturbance. Factor analysis of the CORE in an acute episode of psychotic depression. A two-factor solution, explaining 76.9% of the total variance, emerged. Factor 1 corresponded to the CORE's retardation and non-interactiveness items and Factor 2 corresponded to the agitation items. Internal consistency reliability was 'excellent' for Factor 1 but 'questionable' for Factor 2. Abstract: The CORE instrument is commonly used to measure psychomotor disturbance. We examined the factor structure of the CORE in 266 adults with an acute episode psychotic depression, a disorder with a high rate of psychomotor disturbance. Exploratory factor analysis identified a two-factor solution: Factor 1 corresponded to the CORE's retardation and non-interactiveness items and Factor 2 corresponded to its agitation items. Internal consistency was excellent for Factor 1 but questionable for Factor 2. These findings suggest that the CORE's retardation and non-interactiveness items should be combined in one subscale when assessing patients with an acute episode of psychotic depression.