Differential predictors of pain and disability in patients with whiplash injuries.
The psychological predictors of pain and disability were examined in a sample of people who sustained whiplash injuries during rear-end motor vehicle accidents. Sixty-five patients referred to a specialty pain clinic with a diagnosis of whiplash injury completed measures of depression, anxiety, catastrophizing, pain and perceived disability. Regression analysis revealed that psychological variables accounted for 18% of the variance in pain ratings. The magnification subscale of the Pain Catastrophizing Scale was the only variable that contributed significant, unique variance to the prediction of pain. Psychological variables accounted for 37% of the variance in perceived disability scores. In the latter analysis, however, none of the independent variables contributed significant, unique variance to the prediction of perceived disability. Psychological variables accounted for significant variance in disability ratings, even when controlling for pain intensity. Discussion focuses on the need to draw clearer distinctions between determinants of pain and disability, and directions for interventions aimed at minimizing disability following whiplash injury are suggested.