Reliable patient reported outcome measures (PROM's) for symptom assessment in irritable bowel
syndrome are essential in order to investigate natural disease course and potential treatment
options aimed at symptom improvement, since biological markers are currently unavailable.
Currently used symptom assessment methods, i.e. end-of-day or end-of-week questionnaires,
have considerable limitations. The Experience Sampling Method (ESM), an electronic
questioning method characterized by random and repeated, momentary assessments in the
subject's current state and environment, might overcome these limitations. Aim of this study
is to validate an IBS-specific electronic patient-reported outcome measure, based on the
Experience Sampling Method-principle, for symptom assessment in IBS.