Objective: This study attempts to clarify the relationship between depression and the cognitions of chronic pain patients. It was hypothesized that the ambiguity and desirability of self-rated traits would significantly predict level of depression.Design: The study incorporated a correlational design in which subjects rated a number of traits as they pertained to themselves and completed questionnaires on negative affect and pain.Setting: Subjects were recruited from a Spine Program and the Orthopaedic Clinic, at a tertiary care facility at the University of Florida.Subjects: Fifty-eight chronic pain patients, two thirds of whom had primary back pain, were recruited for the study.Outcome Measure(s): All subjects completed a Beck Depression Inventory and McGill Pain Questionnaire, and rated themselves on 28 traits characterized by the dimensions of desirability and ambiguity.Results: A hierarchical regression analysis indicated that the subjects' self-ratings on ambiguous negative traits significantly predicted level of depression.Conclusions: Patients with chronic pain are more likely to acknowledge undesirable traits in themselves when they have higher levels of depression when the pain level was controlled. These findings may have important implications for the cognitive-behavioral treatment of chronic pain patients.