Overactivity assessment in chronic pain: The development and psychometric evaluation of a multifaceted self-report assessment

Background: Overactivity in the context of chronic pain (i.e. activity engagement that significantly exacerbates pain) is an important clinical issue that has gained empirical attention in the last decade. Current assessment concepts of overactivity tend to focus on frequency to quantify the severity of the pain behaviour. This study aimed to develop and validate a more comprehensive self-assessment, the Overactivity in Persistent Pain Assessment (OPPA). Methods: A sample of 333 individuals with chronic pain completed the OPPA. A subset of 202 individuals also completed a set of existing measures of pain-related outcomes and activity patterns. The remaining 131 participants were provided with a second copy of the OPPA to fill in one week following their initial assessment. Results: A principal component analysis confirmed that the OPPA items were best represented by a single construct. The OPPA was found to correlate with pain-related measures in an expected way that is supported by both theory and qualitative data. When compared to existing overactivity measures, the OPPA was the only measure to contribute significantly to the regression models predicting higher levels of pain severity, more pain interference and lower levels of activity participation after controlling for age, gender and activity avoidance. In addition, the OPPA scale exhibited acceptable internal consistency and good test–retest reliability. Conclusion: The results of this study reinforce the potentially important role of overactivity in the maintenance of pain-related suffering and supports a corresponding assessment tool with preliminary psychometric evidence for clinical and research applications. Significance: This study deconstructs the overactivity concept and develop a corresponding assessment based on five quantifiable severity features: severity of pain exacerbation, maladaptive coping strategies used, impact on occupational performance, recovery time and frequency. Results of the psychometric evaluation indicate that this comprehensive assessment of overactivity severity features may be necessary to understand the impact of overactivity on pain severity and physical functioning from both a clinical and research perspective.