The Patient Simple Clinical Colitis Activity Index (P-SCCAI) can detect ulcerative colitis (UC) disease activity in remission: A comparison of the P-SCCAI with clinician-based SCCAI and biological markers

To develop a patient-based Simple Clinical Colitis Activity Index (P-SCCAI) of ulcerative colitis (UC) activity and to compare it with the clinician-based SCCAI, C-reactive protein (CRP) and Physician's Global Assessment (PGA) of UC activity. Monitoring UC activity may give patients disease control and prevent unnecessary examinations.Consecutive UC patients randomly completed the P-SCCAI either before or after consultation. Gastroenterologists assessed patients' UC activity on the same day. Overall agreement between SCCAI and P-SCCAI was calculated with Spearman's Rho and Mann-Whitney U test. Agreement regarding active disease versus remission and agreement at domain level were calculated by percent agreement and kappa (κ).149 (response rate 84.7%) UC patients participated. P-SCCAI and SCCAI showed a large correlation (rs=0.79). The medians (IQR) of the P-SCCAI (3.78;0-15) tended to be higher than those of the SCCAI (2.86;0-13), although this difference did not reach statistical significance (z=1.71| p=0.088). In 77% of the cases the difference between clinicians' and patients' scores was not clinically different (i.e.≤2). Percentage agreement between clinicians and patients, judging UC as active or in remission, was 87%, rs=0.66, κ=0.66, indicating a substantial agreement. In general patients tended to report more physical symptoms than clinicians. C-Reactive protein (CRP) was found to have a significant association with both P-SCCAI and SCCAI (κ=0.32, κ=0.39 respectively) as was PGA (κ=0.73 for both indices).The P-SCCAI is a promising tool given its substantial agreement with the SCCAI and its feasibility. Therefore, P-SCCAI can complement SCCAI in clinical care and research.