Establishing the Reliability, Validity, and Prognostic Utility of the Momentary Pain Catastrophizing Scale for Use in Ecological Momentary Assessment Research.

Despite the marked increase in ecological momentary assessment research, few reliable and valid measures of momentary experiences have been established. The goal of this preregistered study was to establish the reliability, validity, and prognostic utility of the momentary Pain Catastrophizing Scale (mPCS), a 3-item measure developed to assess situational pain catastrophizing. Participants in 2 studies of postsurgical pain outcomes completed the mPCS 3 to 5 times per day prior to surgery (N = 494, T = 20,271 total assessments). The mPCS showed good psychometric properties, including multilevel reliability and factor invariance across time. Participant-level average mPCS was strongly positively correlated with dispositional pain catastrophizing as assessed by the Pain Catastrophizing Scale (r = .55 and .69 in study 1 and study 2, respectively). To establish prognostic utility, we then examined whether the mPCS improved prediction of postsurgical pain outcomes above and beyond one-time assessment of dispositional pain catastrophizing. Indeed, greater variability in momentary pain catastrophizing prior to surgery was uniquely associated with increased pain immediately after surgery (b = .58, P = .005), after controlling for preoperative pain levels and dispositional pain catastrophizing. Greater average mPCS score prior to surgery was also uniquely associated with lesser day-to-day improvement in postsurgical pain (b = .01, P = .003), whereas dispositional pain catastrophizing was not (b = -.007, P = .099). These results show that the mPCS is a reliable and valid tool for ecological momentary assessment research and highlight its potential utility over and above retrospective measures of pain catastrophizing. PERSPECTIVE: This article presents the psychometric properties and prognostic utility of a new measure to assess momentary pain catastrophizing. This brief, 3-item measure will allow researchers and clinicians to assess fluctuations in pain catastrophizing during individuals' daily lives, as well as dynamic relationships between catastrophizing, pain, and related factors.