A fourth empirically derived cluster of chronic pain patients based on the multidimensional pain inventory: evidence for repression within the dysfunctional group.

The authors proposed that chronic pain patients with repressive defenses are not represented in current 3-cluster solutions of the Multidimensional Pain Inventory (MPI; R. D. Kerns, D. C. Turk, & T. E. Rudy, 1985) and that such a group can be distinguished by using a measure of defensiveness together with subscales of the MPI. They expected these patients to be described both by high defensiveness and by elevated pain and disability but minimal emotional distress. For 178 pain patients, hierarchical cluster analyses were performed on the MPI and Balanced Inventory of Desirable Responding (D. L. Paulhus, 1984). A 3-cluster solution replicated past findings in identifying dysfunctional, interpersonally distressed, and adaptive coper groups. A 4-cluster solution fit the data better, with a repressor group described by high pain, low activity and low distress emerging from the dysfunctional group. Profile analysis of validation measures showed that repressors scored comparably with dysfunctional patients on somatic symptoms of depression, pain severity, and perceived disability but significantly higher on these factors than the adaptive copers. Repressors scored comparably with adaptive copers on cognitive-affective symptoms of depression, anxiety, and anger but significantly lower on these variables than dysfunctional patients. Repressors also reported greater pain severity and perceived disability relative to their reports of negative affect, whereas dysfunctional and adaptive coper groups exhibited no such disparities. Without a measure of defensiveness, the MPI may misclassify a distinct group of patients as dysfunctional, but who readily endorse physical symptoms yet report low levels of emotional distress.

Cognitive-Behavioral Factors in the Management of Chronic Low Back Pain: Conceptualization and Evidence of Treatment Efficacy.

The biomedical and psychogenic models of chronic pain view chronic low back pain (CLBP) in terms too extreme to account for the many factors that contribute to its development and maintenance. A cognitive-behavioral model depicts CLBP not merely in terms of sensory information or psychiatric disturbance, but in terms of well-validated principles that govern perception and behavior. Evidence from correlation, prospective, and experimental studies shows that CLBP can be explained in large measure by 1) the manner in which noxious stimuli are attended to and interpreted; 2) the degree to which certain behaviors become conditioned stimuli for fear responses; and 3) how environmental contingencies increase and decrease the frequency of maladaptive and adaptive behaviors. From this basic research, interventions have been designed to alter maladaptive cognitions and problematic behavioral contingencies. These appear quite effective in alleviating pain, decreasing disability, and lifting mood; more effective perhaps than standard medical management. Although further work is still needed, the case for a cognitive-behavioral model for the conceptualization of CLBP is strong and grows stronger with emerging research.