PRO2 CD (Version 2 | 10-2025)

Clinical intent

The PRO2 is a Patient-reported outcome derived from the Crohn's Disease Activity Index (CDAI) and determines the current severity of Crohn’s disease[1,2].

This second version of the PRO2, added in October 2025, is specifically for Crohn's disease and was developed in collaboration with AZ Maria Middelares for benchmarking purposes with other Belgian hospitals. This instrument may deviate from the original PRO2.

Calculation

PRO2 CD Score

Both items are multiplied by a factor for scoring purposes (2 for stool frequency and 5 for abdominal pain). Then they are summed to get the total score.

PRO2 CD Score = (Q1 * 2) + (Q2 * 5)

Alert

An alert is triggered when both of the following conditions are met:

• PRO2 CD score > 14, AND
• PRO2 CD score increase ≥ 5 compared to baseline

If a baseline score is not provided to the calculator, the alert will always return false.

References

[1] Jairath V, Khanna R, Zou GY, Stitt L, Mosli M, Vandervoort MK, D'Haens G, Sandborn WJ, Feagan BG, Levesque BG. Development of interim patient-reported outcome measures for the assessment of ulcerative colitis disease activity in clinical trials. Aliment Pharmacol Ther. 2015 Nov;42(10):1200-10. doi: 10.1111/apt.13408. Epub 2015 Sep 21. PMID: 26388424.

[2] de Jong MJ, Huibregtse R, Masclee AAM, Jonkers DMAE, Pierik MJ. Patient-Reported Outcome Measures for Use in Clinical Trials and Clinical Practice in Inflammatory Bowel Diseases: A Systematic Review. Clin Gastroenterol Hepatol. 2018 May;16(5):648-663.e3. doi: 10.1016/j.cgh.2017.10.019. PMID: 29066372.