Developing a nomogram for postoperative delirium in elderly patients with hip fractures

Figure 1 Feature screening and Venn diagram analysis based on Lasso regression, support vector machine, and random forest. A: Important features and their coefficients screened out by Lasso regression; B: Important features and their importance scores screened out by support vector machine; C: Important features and their impact on model accuracy screened out by random forest; D: The Venn diagram shows the features commonly screened out by the three methods, including age, previous history of cognitive impairment, preoperative red blood cell count, preoperative albumin, preoperative hemoglobin, preoperative platelet count, and intraoperative blood loss. ASA: American Society of Anesthesiologists; SVM: support vector machine; COPD: Chronic obstructive pulmonary disease; BMI: Body mass index.