RESUMO
OBJECTIVE AND DESIGN: In a randomized controlled study, we investigated whether pain anticipation and fear-avoidance beliefs will lead to behavioral avoidance. PATIENTS: Fifty patients with chronic low back pain (CLBP) performed a simple leg-flexion task. Before the test, members of a control group were informed that the movement would not result in any increase of pain, whereas experimental group participants were told that a slight increase of pain could occur. OUTCOME MEASURES: All patients completed the Fear-Avoidance-Beliefs Questionnaire (FABQ) and the Pain Disability Index (PDI). As dependent variables, different behavioral performance parameters were registered by a computerized protocol: number of flexion movements, mean range of motion, and mean work ratio. Furthermore, patients were asked about their pain intensity as well as their fear (at the moment) and finally were asked to judge the unpleasantness of the experiment (using visual analogue scales for each of the three variables). RESULTS: Inducing pain anticipation (by instruction) led to significantly lower levels of behavioral performance as well as increased pain intensity and fear during the test. Behavioral performance was significantly correlated with fear-avoidance beliefs. CONCLUSIONS: Results confirm that pain anticipation and fear-avoidance beliefs significantly influence the behavior of patients with low back pain in that they motivate avoidance behavior. Therapists must be aware of the powerful effects of cognitive processes, which can give rise to fear of pain and, consequently, avoidance behavior.
RESUMO
Fearful avoidance of physical activities is a major factor in low back pain (LBP) and disability. In 1993 Waddell et al. developed the Fear-Avoidance Beliefs Questionnaire (FABQ) focusing on patients' beliefs about how physical activity and work affect LBP. The focus of our study was to analyse and validate the German version of the FABQ. Three-hundred and two consecutive LBP outpatients participating on a functional restoration programme filled in the FABQ. Factor analysis yielded three factors which accounted for nearly 65% of the total variance of the questionnaire. Whereas the factor 'physical activity' (8.9% of the variance) remained the same as in the English version, the second factor of the original version split into two: one related to, 'work as cause of pain' (43.4% of the variance) and the other to patients' assumptions of their probable return to work (11.8% of the variance). Both work-related subscales showed a good internal consistency (alpha = 0.89, resp. alpha = 0.94), whereas the consistency of the subscale 3 'physical activity' was only modest (alpha = 0.64). Test-re-test reliability score was fair to good for the whole scale (r = 0.87;n = 30). Regression analysis demonstrated that fear-avoidance beliefs account for the highest proportion of variance (35%) regarding disability in activities of daily living and work loss. Patients out of work demonstrated more fear-avoidance beliefs in comparison to those who were still working. It can be concluded that the German version of the FAQB is a reliable and valid instrument, but it shows a different factor structure from the original English version. The FABQ has been proven to identify patients with maladaptive beliefs which have to be focused on in proper treatment.
