The Illness Intrusiveness Rating Scale: A measure of severity in individuals with hyperhidrosis

Objective: We estimated the reliability and validity of the Illness Intrusi veness Ratings Scale (IIRS) in hyperhidrosis, using an electronic mail form of administration. Methods: Recent contributors to an electronic mail disc ussion group on hyperhidrosis responded to the IIRS, questions about surgic al history, items designed to assess severity, and demographic questions, o n two occasions four weeks apart. A variety of hypotheses regarding the rel ationships between these variables were constructed a priori. Results: Sixt y-eight people replied on two occasions. Internal consistency was high (Cro nbach's alpha 0.88), as was test-retest reliability (kappa 0.89). The total IIRS score correlated with a global severity question (0.61; p < 0.001). T otal IIRS score was lower in participants who had previously had surgery fo r hyperhidrosis, compared with those who had not (47 vs. 36; p = 0.02), and changed dramatically in the direction of diminished severity in four patie nts who underwent surgery during the course of the study (54 vs. 17; p = 0. 01). Weak-to-moderate correlations were observed between total score and us e of topical preparations, use of medications, number of clothing changes d uring a day, and limitations in choice of wardrobe. Conclusions: The IIRS i s both reliable and valid in the assessment of patients with hyperhidrosis. A novel form of administration does not appear to affect its properties.