Predictive capacity of pain beliefs and catastrophizing in Whiplash Associated Disorder

Beliefs about pain are known to be important factors in recovery, most notably in LBP. Relatively less is known about the role of pain beliefs in Whiplash Associated Disorder (WAD). The widely advocated cognitive-behavioural approach to pain management necessitates cognitive factors such as pain beliefs be examined, even early after injury. The primary purpose of this study was to explore the predictive capacity of early post-injury pain beliefs and catastrophizing in patients with WAD.

Patients (n=72) undergoing treatment for acute WAD in physical therapy and chiropractic clinics were invited to participate in the study. Research participants were asked to complete measures of beliefs (Survey of Pain Attitudes (SOPA) and Pain Beliefs and Perception Inventory (PBPI)) and catastrophizing (Pain Catastrophizing Scale) at baseline (within 6 weeks of injury), and 3 and 6 months post-injury. In addition, pain severity and self-reported disability using the Whiplash Disability Questionnaire (WDQ) were recorded at each measurement occasion. Baseline belief and catastrophizing scores were examined for their relationship with future pain and disability using multiple linear regression.

Expectancy beliefs (PBPI Permanence and SOPA Medical Cure) were negatively correlated with pain intensity at 6-months and uniquely accounted for 16% and 14% of explained variance, respectively, after controlling for baseline pain intensity, age, sex and history of WAD. Consistent with previous research, catastrophizing was also found to be predictive of future pain. The amount of unique variance explained by beliefs in the prediction of future disability was modest after controlling for baseline disability, age, sex and history of WAD.

These results suggest that expectancy beliefs are potentially important constructs to include in future explanatory prognosis studies. The Medical Cure and Permanence subscales of the SOPA and PBPI are tools that could be used to measure these expectancy constructs.