Flowchart of patients selected for analysis, illustrating the number of patients at each stage of the study. Flowchart of patients selected for analysis, illustrating the number of patients at each stage of the study. Most patients were excluded because they did not return the questionnaires at baseline. We completed 11 re-experience scores, 23 avoidance scores and 15 arousal scores by the mean of the non-missing items. Two Post-traumatic Diagnostic Scales could not be used for analysis because all three subscales (re-experience, avoidance and arousal) had more than one missing value. Rafael J A Cámara et al. Frontline Gastroenterol 2011;2:2-9 Copyright © BMJ Publishing Group Ltd & British Society of Gastroenterology. All rights reserved.