Page 129 - THE PERCEPT STUDY Illness Perceptions in Physiotherapy Edwin de Raaij

A multiple baseline single-case experimental design
Design
A multiple baseline SCED was applied. Participants completed repeated measurements dur- ing pre-treatment (phase A), during the treatment period (phase B) and a post-treatment period (phase A’). During all three phases of the study, the patients were asked to complete an online questionnaire (Appendix C), twice a week in phase A and weekly in phases B and A’. Phase A acts as a control phase (no treatment given) for comparison with phases B and A’. The duration of phase A was three weeks with five to six measures. During phase B the pa- tients received a matched-care treatment package (paragraph 2.3) by their physiotehrapist. The number of sessions was left to the discretion of the physiotehrapist, and therefore the duration of this phase varies accross patients. The content of the matched-care was response guided, meaning the intervention was based on the outcomes of the online questionnaires, which were administered by the patient the day before each consecutive intervention. The post-intervention period phase A’ took 12 weeks, independent of the duration of phase B. The study followed the guidelines of the declaration of Helsinki and the code of conduct for scientific research of our institute and was approved by the Medical Ethical Committee of the University of Applied Sciences, Utrecht (ref. no. 950002019).
Patients
Eligible patients for this study were enrolled from six different primary care physiotherapy practices in The Netherlands within a period of three months. The invitation and treatment were performed by the same physiotherapist. Resulting from the design of the SCED, patients had to be willing to undertake phase A, which meant a three week wait while completing a total of five to six outcome measures before the first treatment in the clinic. We foresaw that this ‘waiting’ for a first treatment might be unattractive to patients and therefore of influence on the number of patients wanting to participate. This concern was addressed in a patient information letter by explaining the purpose of phase A; to determine a detailed baseline assessment which is important to design the match-care intervention. Inclusion criteria were age 18 years or older, LBP for at least 3-months, experiencing a movement problem in daily life due to LBP and having dysfunctional levels of at least one out of eight IP dimensions. Dysfunctional levels of IPs were based on a secondary analysis of an earlier study on the associations of IPs with patient burden with musculoskeletal pain10 (Appendix A). We chose the fourth quartile as threshold (box 1), expecting these high-level scores to represent dys- functional IPs. When an eligible patient was identified at the clinic, a patient information letter was presented in which the study design was outlined. From there on, patients were free to choose whether to participate in the study, without any risk of being withheld from physiotherapy care.
127
7