Other significant predictors of critical care admission on the univariate analysis were presence of gallstones (OR 0.43, 95% CI 0.20 to 0.90, p = 0.026) and CRP concentrations of ≥120 mg/L (OR 1.01, 95% CI 1.00 to 1.02, p = 0.0001). Here, CRP is linked to gallstones.