Waddell's nonorganic signs and Minnesota Multiphasic Personality Inventory profiles in patients with chronic low back pain

Study Design. An analysis of clinical data gathered at an orthopedic outpatient clinic is presented. Objective. To examine the relationship between Waddell scores and the Minnesota Multiphasic Personality Inventory response patterns. Summary of Background Data. Waddell's study of nonorganic signs of low back pain showed consistent correlations with Minnesota Multiphasic Personality Inventory scales 1 to 3. Methods. A Waddell score was obtained from 507 consecutive patients with chronic low back pain to whom an Minnesota Multiphasic Personality Inventory also was administered. The sample was divided into those patients with a high Waddell score (high waddell score = 3 to 5) and those with a low Waddell score (low waddell score = 0 to 2); men and women were scored separately. Results. Among male patients, statistically significant differences were found between the high Waddell score and low Waddell score groups on Minnesota Multiphasic Personality Inventory scales 1, 3, and 8, but among females, differences were statistically significant only on scale 8. Conclusions. Correlations between the Waddell score and the first three scales of the Minnesota Multiphasic Personality Inventory were not fully replicated. The difference between the high Waddell and low Waddell groups on scale 8, however, was significant for men and women.