Perfectionism as an Explanatory Construct in Comorbidity of Axis I Disorders

Understanding comorbidity is an important challenge for psychopathology researchers and diagnostic systems given the repeated finding of very high comorbidity rates among Axis I disorders in psychiatric samples. This paper proposes that perfectionism may be a critical factor for understanding levels of comorbidity, and a conceptual argument for the importance of perfectionism as an explanatory construct for comorbidity is advanced. The link between perfectionism and comorbidity in a large sample of patients (N = 345) who attended an anxiety disorders clinic is examined using a variety of methods. Diagnoses were established using the Structured Clinical Interview for DSM-IV (SCID-IV), and perfectionism was assessed using both the Hewitt and Flett and Frost Multidimensional Perfectionism Scales. Overall, scores on both the Hewitt and Flett and Frost perfectionism scales were correlated with the number of diagnoses, and a logistic regression analysis, controlling for current symptoms, showed that maladaptive evaluative concerns perfectionism in particular predicted higher levels of comorbidity.