Validity at Follow-up
Of the 52 patients contacted for follow-up, 33 (63.5%) responded after a median of 1.2 years (IQR=0.92, 1.9) after study entry. Of the 33 responders, 4 (12.1%) patients’ CU has since resolved. Of the remaining patients, 28 completed the UCT and 27 completed the CDLQI as well, with median scores of 13.5 (IQR=11.8-15.0) and 2.0 (IQR=1.0-5.0), respectively. The UCT had respectable internal consistency in the evaluation of CU (Cronbach’s α=0.74 [95%CI: 0.59, 0.89]). At follow-up, the UCT moderately correlated with CDLQI scores (r=-0.59, P<0.01) and could distinguish between different disease severities by Kruskal-Wallis test (P<0.01). Moreover, the UCT had excellent discrimination of poorly controlled urticaria (Figure 1E, AUC=0.81 [95%CI: 0.56, 1.00]), with an optimal cut-off of ≤9 [sensitivity=87.5%, specificity=66.7%]. Patients who started taking or increased their dose of sgAHs after study entry (N=14) had a greater increase in UCT scores from study entry to follow-up than patients who decreased or ceased sgAHs (N=12) (mean change in UCT=5.3 versus 2.1, respectively, P=0.04).