The factor structure and subscale properties of the pain catastrophizing scale: are there differences in the distinctions?

Introduction: Increasingly, studies have documented the negative impact of pain catastrophizing on health outcomes. The Pain Catastrophizing Scale (PCS) has been the measure of choice for many of these studies. The PCS provides 3 subscales for measuring pain catastrophizing: rumination, magnification, and helplessness. Factor analytic investigations of these factors have been limited by the sample size and relevance, and results have been inconsistent. No study has directly estimated the added value of subscale scoring of the PCS compared with scoring it as a single measure. Objective: The purpose of this study was to evaluate the dimensionality of PCS responses in a sample of patients with chronic pain (N = 8370). Methods: Data were randomly halved, and results were cross-validated. Both traditional factor analysis and traditional factor analyses were conducted. Results: Findings based on common factor analyses and on bifactor analyses supported the essential unidimensionality of PCS responses. In the bifactor analyses, the general factor accounted for 96% of the explained common variance in the modeling sample. After extracting the general factor, helplessness, magnification, and rumination subscales accounted for 7.0%, 0.0%, and 15%, respectively. Conclusion: The results do not necessarily disconfirm helplessness, magnification, and rumination as clinically meaningful theoretical distinctions. However, the PCS (at least as presently constructed) fails to discriminate these distinctions. Joint efforts in theory and measurement science could illuminate the role that posited "kinds" of pain catastrophizing play in individuals' pain experiences.