Page 79 - THE PERCEPT STUDY Illness Perceptions in Physiotherapy Edwin de Raaij

Demographic characteristics and clinical variables collected in daily practice included age, gender, pain intensity (PI), and the completed Patient-Specific Functional Scale (PSFS) for limitations in physical functioning. The known prognostic factors of persistent pain were measured with questions about the number of pain sites, pain duration, and the Four- Dimensional Symptom Questionnaire (4DSQ). Finally, illness perceptions (participants’ beliefs about their MSP) were measured using the Brief Illness Perception Questionnaire Dutch Language Version (Brief IPQ-DLV).
Study population
Over a period of three months, all consecutive patients, if eligible, were asked to participate in the study. Included were patients with MSP, aged between 18 – 75 years. Exclusion criteria were the presence of red flags, specific musculoskeletal diseases or physiotherapy treatment within six months prior to the first consultation. The study was approved by the Medical Ethical Committee of the Medical Ethical Committee of the University of Applied Sciences, Utrecht (ref. no. 430002016) and all participating patients signed an informed consent form.
Measurements Overview
In this study, pain intensity (PI) and the Patient-Specific Functional Scale (PSFS) for limitations
in physical functioning were the primary outcomes. IPs were the observed exposure variables
of primary interest. Based on published research, multiple pain sites, pain duration, and the
psychological factors somatization, distress, anxiety, and depression were considered to be
important prognostic factors for the persistence of MSP and were therefore included in this study23,14,22,1,20 .
Pain intensity
To measure the average PI in the last 24 hours, we used the Numeric Rating Scale (NRS). This is an 11-point rating scale in which 0 is no pain and 10 the worst pain imaginable11.
Patient-Specific Functional Scale
Physical functioning was assessed with the PSFS, which is known to be a feasible and reliable instrument27,2.
Multiple pain sites
Participants were asked to register the number of different sites in which they experienced pain. We categorized the outcomes into 2 groups:
• 1 pain site
• ≥ 2 pain sites
A cross-sectional study
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