Multidimensional Inventory of Hypochondriacal Traits: An Examination of a Bifactor Model and Measurement Invariance Between Those With and Without a Self-Reported Medical Condition.

The Multidimensional Inventory of Hypochondriacal Traits (MIHT) is a self-report measure that assesses four interrelated domains of health anxiety (i.e., Cognitive, Behavioral, Perceptual, Affective). Prior research has supported a correlated four-factor model, as well as a hierarchical model, in which each of the four factors load onto the higher order health anxiety construct. However, a bifactor modeling approach has yet to be used to examine the factor structure of the MIHT. Results supported a bifactor model of the MIHT in three different samples (i.e., unselected based on current medical status [ n = 824], and those with [ n = 348] and without [ n = 354] a self-reported medical condition). The MIHT appears to be strongly multidimensional, with three of the four subscales providing substantive value. Confirmatory factor analysis supported the configural and metric/scalar invariance of the bifactor model between those with and without a self-reported medical condition. Results provide support for a bifactor conceptualization of the MIHT and the invariance of that model across levels of current health status.