Page 178 - THE PERCEPT STUDY Illness Perceptions in Physiotherapy Edwin de Raaij

Appendix
These associations are not strong, and all studies are of a moderate methodological quality. The associations of IPs with pain intensity and physical functioning were consistent across various musculoskeletal disorders, such as rheumatoid arthritis, low back pain, different forms of chronic pain, and fibromyalgia.
Ad 2: In the systematic review, two studies showed a predictive value for the illness perceptions dimensions Consequences, Personal Control, Treatment Control, Coherence and Emotional Response for higher pain intensity six months after the baseline measurements. Three studies reported a predictive value for the IP dimensions Consequences, Timeline and Identity for higher pain intensity between six and 12 months after the baseline measurements. No studies included a follow-up more than twelve months. The predictive values found are not strong and of moderate methodological quality.
Studies on whether illness perceptions can predict limitations in physical functioning were found more often. Nine studies report a predictive value of all IPs dimensions except Treatment Control for more limitations in physical functioning six months after baseline measurements. One study shows a predictive value of the IPs dimensions Timeline, Personal Control and Identity for more disabilities in physical functioning between six and twelve months after baseline measure. Two studies report predictive values of IPs dimensions Consequences, Timeline, Treatment Control and Identity more than twelve months after baseline measurements. It must be noted that the predictive values found are not strong and the methodological quality of the studies is moderate.
Chapter 4
We performed a cross-sectional study among 658 patients with MSP in 29 primary care physiotherapy settings. First, we were interested in whether the IPs that patients have about MSP differ as pain persists longer. Pain duration was classified as follows: acute pain (< 7 weeks), subacute pain (7-13 weeks) and persistent, chronic pain (> 13 weeks). Significant differences were found in IPs with regard to pain duration but these differences were small, less than two points on a 0-10 scale. Only the IP dimension Timeline shows a larger difference between acute and persistent pain, namely three points on a 0-10 scale. Patients who had experienced pain for more than 13 weeks also scored higher on the question ‘How long do you think your pain will last?’
Secondly, we were interested in the association between IPs and pain intensity and the association with limitations in physical functioning. We took into account other known prognostic factors like pain intensity, duration of pain, degree of disabilities in daily life, located in more than two pain sites and psychological factors of distress, somatization, depression and fear. By means of a multiple linear regression, adjusted for gender, age and
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