Zsa Zsa Weerts

Chapter 7 148 Additionally, a per-protocol (PP) analysis was performed. The PP-population included all randomized patients who had at least 80% adherence to treatment and had completed the treatment period. A detailed description of the statistical analysis of secondary outcomes, for which a multiplicity correction was applied resulting in a significance level of <0.025, is given in the Supplementary Material . Statistical analyses were carried out using IBM (Armonk, NY, USA) SPSS statistics 25.0 for Macintosh. Results Patient disposition, demographics, and baseline characteristics Between August 2016 and March 2018, 622 patients were screened for participation in this study of whom 190 were randomized ( Supplementary Figure S7.2) . One patient was erroneously randomized, i.e. without having a mean worst abdominal score of more than 3 during the pre-treatment period, and excluded from further analyses. Therefore, the modified ITT-population consisted of 189 patients. Baseline characteristics are shown in Table 7.1 and were balanced across treatment groups (mean overall age 34.0 years old, standard deviation 13.3, 77.8% female, 95.8% Caucasian, 57.7% primary care). In total, 11 patients withdrew from the study: nine discontinued as a result of adverse events, one because of insufficient therapeutic response, and one for personal reasons. Of the small-intestinal release peppermint oil group, 90.3% was adherent to study treatment during the complete treatment period or until discontinuation, compared with 92.1% of the ileocolonic release peppermint oil group, and 96.9% of the placebo group ( P =0.330 between groups, Supplementary Table S7.1 ). Overall compliance to the digital diary was high and did not differ significantly between small-intestinal release peppermint oil, ileocolonic release peppermint oil, and placebo, being 88.3% ( P =0.561), 85.3% ( P =0.357), and 87.2% during the complete treatment period or until discontinuation ( Supplementary Table S7.1 ) . Compliance to the web- based questionnaires was also high : only a single patient did not complete the questionnaires at the end of the treatment period. All other patients completed the symptom questionnaires with no missing values until the end of the study or until discontinuation.