Behavioral Test (BAT-Back): Preliminary Evidence for a Successful Predictor of Treatment Outcome After Exposure Treatment for Chronic Low Back Pain.

OBJECTIVES

Although several questionnaires assessing fear of movement exist, it is still a challenge to identify individuals who might benefit more from exposure for chronic pain than from other psychological approaches and vice versa. Psychological approaches to chronic pain cannot advance toward the often called-for "tailored approaches" because of limited knowledge about treatment predictors. Our aim was to evaluate the additional predictive value of avoidance behavior based on behavioral observation.

METHODS

This study examined pretreatment self-report and behavioral measures as predictors of treatment outcome for n=43 patients experiencing disabling chronic low back pain, who took part in a randomized controlled trial in which they received 10 to 15 sessions of exposure treatment. Only patients with elevated fear avoidance based on self-report measures were included. Data were analyzed using regression analyses and classification and regression trees.

RESULTS

Regression analyses showed that higher avoidance behavior at pretreatment as measured by the Behavioral Avoidance Test-Back Pain (BAT-Back) significantly predicted reduction in global disability (with a small to medium effect), but not in specific disability. Self-report measures failed to predict treatment success for both outcome measures. Classification and regression trees divide subgroups who might benefit from exposure treatment through a BAT-Back score of >22 for Pain Disability Index.

DISCUSSION: There is some preliminary evidence that pretreatment avoidance behavior might be an indicator for reduction in global disability after exposure treatments in patients experiencing disabling chronic low back pain and elevated fear avoidance. We identified preliminary cutoff scores that need further investigation.