Timing matters: recommendations for outcome assessment in real-world evidence studies of Crohn's disease

Real-world evidence (RWE) studies complement randomized trials by assessing treatment effectiveness and safety in routine clinical practice. In Crohn's disease (CD), heterogeneous disease progression makes standardized timing of outcome assessment critical, yet guidance is limited.

We conducted a two-round Delphi survey with international inflammatory bowel disease experts to identify clinically meaningful time points for 10 priority outcomes across four clinical scenarios: during and after the first year, with and without advanced therapy.

Baseline and 12 months were identified as essential time points across all treatment contexts. Intermediate assessments at 3 and 6 months were recommended for dynamic outcomes (eg, biomarkers, clinical remission), while annual evaluations were suggested for slowly evolving outcomes (eg, colorectal cancer risk, CD-related surgeries). Timing preferences varied by treatment exposure and disease activity phase.

We provide the first expert-endorsed temporal framework for outcome assessment in RWE studies of CD. Standardized measurement timing can enhance study comparability and methodological rigor, supporting more consistent interpretation of real-world data. Claims are limited to framework development and do not extend to direct clinical or regulatory impact.