Moreover, patients correctly identified as complicated appendicitis had higher CRP levels (median 139 (IQR 70–217) versus 69 mg/L (IQR 35–134), respectively) and longer duration of symptoms before presentation (proportion of patients with complaints ≥ 3 days: 50.9% vs 23.3%, respectively) than those wrongfully classified. The gene discussed is CRP; the disease is appendicitis.