Type D assessment in patients with chronic heart failure and peripheral arterial disease: evaluation of the experimental DS(3) scale using item response theory

Type D personality refers to a clustering of 2 stable personality traits, namely negative affectivity and social inhibition. Currently Type D is standardly assessed using the DS14. An experimental Type D personality scale, the DS((3)), was developed to examine an avenue for assessing Type D more efficiently. The DS((3)) differs from the DS14 in its use of a 3-point Likert scale to rate responses, use of all negatively worded items, and a rearranged presentation of items. This article examines the psychometric properties of this questionnaire by examining its dimensionality, item and scale properties, and cutoff scores to screen for Type D personality. Data from 2 clinical samples were analyzed using item response theory. The results suggest that the DS((3)) is a potentially suitable instrument for Type D assessment. It has high reliability, and Type D personality classification based on this scale corresponds well with the current standard Type D assessment based on the DS14.