[Correspondence] Peripheral blood DNA methylation signatures to predict treatment response in Crohn's disease - Authors' reply

We appreciate the interest in our study from Hui Li and colleagues. Patient selection was a key consideration in the design of our study, requiring a balance between cohort homogeneity and practical feasibility. Because anti-TNF medication is commonly used as first-line therapy, the switch from infliximab to adalimumab is well reflected in our cohort. We acknowledge, in agreement with Li and colleagues, that this introduces an element of heterogeneity. However, it is worth noting that the earlier work by Lin and colleagues,1 which included only patients who were anti-TNF-naive, was unable to develop a pretreatment prediction model independent of dosage.