CRP and appendicitis: Tenderness in the right fossa was found to have the greatest impact on the decision to perform appendectomy with an odds ratio (OR) of 76, followed by raised CRP (OR 47), pain in the right fossa (OR 29), increasing CRP (OR 23), indirect tenderness (OR 19), pain migration (OR 18) and image diagnostics (OR 4) i.e., these items differed the most between patients with appendicitis and those without.