Page 159 - THE PERCEPT STUDY Illness Perceptions in Physiotherapy Edwin de Raaij

tigue, multiple sclerosis, irritable bowel syndrome, psoriasis and hypertension18. Overall, Hag- ger et al.18 report associations of the IP-dimensions Identity, Consequences, Control, Timeline, Coherence and Emotional Response with physical and social functioning. However, the mus- culoskeletal domain is not fully represented in these data. Our systematic review enriches the existing evidence and shows besides low to moderate associations of IPs with MSP and functioning a lack of longitudinal studies to address the possible prognostic value of IPs. Also, we found no studies within primary physiotherapy settings, a setting in which a large number of people with musculoskeletal pain present themselves. To further explore the association and prognostic value of IPs in primary physiotherapy care, we designed a cross-sectional and longitudinal study, see chapters 4 and 5.
Methodological considerations
A strength is that our systematic review was written in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines23 and the Measurement Tool to Assess systematic Reviews checklist33. Details of the protocol for this study were registered with PROSPERO and can be accessed at http://www. crd.york.ac.uk/PROSPERO/display_ re- cord.asp?ID=CRD42016026759. Our study is fully executed as described in the protocol.
A possible explanation for the reported limited to moderate associations of IPs with pain and physical functioning can be found in the validity of questionnaires that were used in the included studies to assess the IPs. All three IPs questionnaires are constructed to explore IPs in a quantitative way, using a Likert Scale or a Numeric Rating Scale. It is debatable if such measures are sufficient enough to assess patients’ IPs about their MSP. As stated earlier in chapter 2, IPs can be explored in more depth by the use of interviews, and may lead to other conclusions about the impact of IPs on pain and physical functioning11, 8.
Practical implications
Based on the cross-sectional studies in our review, we conclude that a higher score on an IP dimension is associated with higher score on pain and limitation in physical functioning. This is consistent among all IPs dimensions. Therefore, we conclude that a higher score on IPs could be indicative for dysfunctional IPs. When taking the methodological consideration about measuring IPs quantitatively into account, we propose the use of an IPs questionnaire at baseline and follow-up with more in-depth assessment of IPs by an interview based on the outcome score of the IPs questionnaire (see also chapter 2).
For clinicians, this suggests that addressing patients’ IPs in this manner may open new possi- bilities for management of MSP, but this needs to be further explored.
General discussion
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