Ires Ghielen

143 BEWARE: Results of the pilot RCT Methods For a detailed description of the methodology, including the intervention protocol, we refer to the article of Ghielen et al. [26]. Study design We conducted an investigator-blind randomized controlled trial. Forty PD patients with WRA were randomly allocated to either the BEWARE training (4 groups of 4-6 patients) or to the treatment as usual (TAU) receiving group physical therapy (4 groups of 4-6 patients). Block-randomization with 2 blocks of 4 was done using concealed opaque envelopes and conducted by an independent investigator. Assessments were conducted prior to the intervention (baseline), directly after the six-weeks intervention (post-treatment) and at 18 weeks follow-up (3 months after completing the intervention). A blinded investigator, who was not involved in the intervention and/or randomization, performed all assessments. Patients Forty participants were recruited from the outpatient clinic of the VU university medical center and through the Dutch Parkinson patient association (see figure 1 for the flow chart according to the CONSORT-statement [27]). Inclusion criteria were: 1) a diagnosis of idiopathic PD according to the UK PD Brain Bank criteria [28]; 2) the presence of one or more wearing-off symptoms, as measured with the 19-item Wearing-Off Questionnaire (WOQ-19) [29]; 3) clinically relevant anxiety, defined by a Beck Anxiety Inventory (BAI) score >26. Patients with cognitive impairment defined as a Mini Mental State Examination (MMSE) score of <24, insufficient motivation for participation, or neurological, orthopaedic or cardiopulmonary problems that could interfere with participation in the view of the researchers, were not eligible for participation. The patients were asked to maintain a stable medication schedule throughout the treatment period of six weeks. To detect a 10% larger reduction in the General Self Efficacy Scale (GSES) in the BEWARE condition compared to TAU, a minimum of 16 patients was required per treatment condition to achieve a statistical power of 80% with a two-tailed significance level set at p<0.05. Considering a maximum dropout of 10%, 36 PD patients (18 per condition) were needed. Interventions Two treatment conditions were investigated in this study: the experimental condition (BEWARE) and the conventional physical therapy (TAU). Both interventions consisted of 12 sessions, each 1-hour long, 2 times per week for 6 weeks. Each group consisted 8