Waddell signs: distributional properties and correlates.
OBJECTIVE: To determine what percentage of patients have none of the five nonorganic behavioral processes known as Waddell signs, and the relational pattern between Waddell signs and somatic complaints, disturbed functional performance, negative treatment attitudes, physical pathology, depression, generalized anxiety, and MMPI-2 validity scales. DESIGN: Case series survey. SETTING: A referral-based multidisciplinary pain center affiliated with a state medical school. PATIENTS: Seventy-five consecutive patients with chronic back pain. INTERVENTION: Medical evaluation and completion of self-report inventories. MAIN OUTCOME MEASURE: Total number of Waddell signs, physical pathology, and pain intensity ratings were assessed by a physician during an initial medical evaluation. Degree of disturbed functional performance and psychological symptoms were assessed by self-report measures at the initial evaluation. RESULTS: Sixty-four percent of the patients had no Waddell signs. Total number of Waddell signs yielded positive and statistically significant correlations (p < or = .05) with depression, disturbed functional performance, somatic complaints, and pain intensity ratings. Correlations of slightly smaller and statistically nonsignificant magnitudes were revealed for Waddell signs with generalized anxiety, negative treatment attitudes, and physical pathology. Waddell signs were unrelated to age, duration of pain, gender, number of lumbar surgeries, and MMPI-2 validity scales. CONCLUSIONS: Taken together, multiple Waddell signs and some of their correlates present various factors that might interfere with optimal response to treatment.