Randomisation and masking
DISEASE
Patients were randomly assigned (1:1:1) to either continue combination therapy (combination group), discontinue infliximab and continue immunosuppressant therapy as monotherapy (infliximab withdrawal group), or discontinue immunosuppressant therapy and continue infliximab therapy as monotherapy (immunosuppressant withdrawal group). Randomisation was stratified according to disease duration before start of the first anti-TNF administration (≤2 years or >2 years), failure of immunosuppressant therapy before the start of infliximab, and presence of ulcers at baseline endoscopy. The patient number and group of each stratum were assigned by a central online randomisation website (Cleanweb). An independent statistician from the Biostatistics Unit of Saint-Louis Hospital (Paris, France) provided computer-generated assignment blocked randomisation lists with the use of a block size of six, unknown to the investigators. Information about allocation was given on the eCRF and confirmed by email. Participants, those assessing outcomes, and those analysing the data were not masked to group assignment.