Comparison of Perfectionism and Tolerance of Ambiguity in the Subtypes of Illness Anxiety Disorder

Objective: Illness Anxiety Disorder (IAD) has two subtypes, care-seeking type, and care-avoidant. There is little information about the differences between the two subtypes.  Methods: This study was carried out to compare perfectionism and tolerance of ambiguity in the subtypes of the IAD. To this end, a causal-comparative design was employed. The statistical population of the study included those clients with symptoms of IAD who were referred to psychiatric and psychological clinics in Urmia city (West Azerbaijan Province, Iran; 2019). After conducting a semi-structured interview, 60 subjects were selected as sample members, using a convenience sampling method. The Perfectionism Inventory (Hill et al., 2004) and the Tolerance of Ambiguity questionnaire (McLain, 1993) were utilized for data collection. The collected data were analyzed by using the multivariate analysis of variance test.  Results: The result showed that the care-avoiding subtype had significantly higher scores on some subscales of perfectionism, including concern over mistakes (F=8.735; P=0.005), need for approval (F=4.988; P=0.029), and organization (F=4.505; P=0.038). On the contrary, the care-seeking type showed a significantly lower tolerance of ambiguity than the care-avoidant type (t=2.689; p=0.001). Conclusion: The findings of this study suggest some subtle differences between the subtypes of IAD. As a result, paying attention to these differences can lead to developing tailored treatments for each of the IAD subtypes.