Page 127 - THE PERCEPT STUDY Illness Perceptions in Physiotherapy Edwin de Raaij

Introduction
For decades now, low back pain (LBP) has been recognized as the main cause of years lived with disabilities40. Managing the global impact of LBP on patients, the increase of economic costs and the impact on society are challenging issues and therefore The Lancet Series on Low Back Pain 2018 included a call for action2,6,14,17. Management of persistent LBP has been proposed to shift from a unidimensional (focused on a patho-anatomical disorder) to a more holistic approach, making the transition from the biomedical model to a more biopsychoso- cial model4,31,32. Following this proposal, a physiotherapy treatment of LBP that incorporates biopsychosocial factors that play an important role in the patients’ LBP has the potential to increase the positive effect of physiotherapy. Examples of such treatment strategies are described in a Cochrane review on behavioral therapy for LBP; operant, cognitive-. and re- spondent strategies19.
Most of the extensive body of knowledge on the management of LBP derives from systematic reviews and randomized controlled trials (RCTs). These designs represent the highest level of evidence in evidence based medicine. In addition, the randomized n-of-1 trials are also recognized as level 1 evidence in the Oxford Center for Evidence-Based Medicine 2011 levels of evidence28,34. The use of evidence from systematic reviews and RCTs is a form of “reference class forecasting” and can be challenging for clinicians when making clinical relevant deci- sions for individual patients22. Does this patient fit within the “reference class” that has been reported to progress well with the intervention?
Recently, the call for a more personalized approach for LBP was made25. Such an approach could be a matched-care intervention, in which patients’ individual prognostic factors for re- covery are assessed, and a response guided treatment package can be designed. A response guided treatment means that the treatment is matched to the ‘risk-profile’ of the patient. Known factors in such risk-profiles are psychological factors like fear of movement39, cata- strophizing33, avoidance38, somberness23 and sleep36. It is hypothesized that such matched- care intervention may result in better treatment outcomes29. In this study we investigate the impact of taking into account another psychological factor in the risk-profile, namely Illness Perceptions’ (IPs), which is the core element of Leventhal’s Common Sense Model of health and Illness Representations (CSM)24 8.
The CSM is a parallel processing model that describes both cognitive and emotional rep- resentations of perceived health threats, leading to patients’ IPs resulting from these health threats. Higher IPs scores reflect a more threatening perception of illness and can be called ‘dysfunctional IPs’. These dysfunctional IPs may mediate or moderate persistent pain and
A multiple baseline single-case experimental design
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