Factor Structure of the Illness Intrusiveness Ratings Scale in Young Adults With Allergies and Asthma

Abstract

Objective. To determine the factor structure of the Illness Intrusiveness Rating Scale in young adults with only allergies versus those with both allergies and asthma to evaluate the domains of impairment associated with these 2 chronic health conditions. Method. A total of 454 young adults with allergies (n = 255) or asthma + allergies (n = 199) between the ages of 18 and 25 (mean = 19.39, standard deviation = 1.34) completed the study questionnaire as a part of a larger study of the psychosocial adjustment of young adults with a chronic health condition. Results. A 3-factor structure (Identity, Intimacy, and Relationships and Personal Development) of the Illness Intrusiveness Rating Scale had better fit than a 1-factor structure. Several modifications to the original 3-factor model improved the fit within this population. Conclusions. The 3-factor model was shown to be effective within young adults with allergies and asthma + allergies with some modifications. The structure of the final model was not invariant across the disease groups, although most of the items (excluding health and religious expression) performed similarly between those young adults with allergies and those with asthma + allergies.