Table 4. Analysis Stratified by Probability of Receiving General Anesthesia
Breslow-Day test for homogeneity of the odds ratio was not significant (P = 0.50). Overall summary odds ratio, 1.03; 95% confidence interval, 0.81–1.32.
* The variables included in the predictive model of anesthesia were age, gender, race, hospital admission year (added as 11 indicator variables), hospital (added as 19 indicator variables), transfer from an acute care hospital, surgical procedure (divided into three groups: internal fixing with pinning, internal fixation other than pinning, total or hemiarthroplasty), history of cardiovascular disease, valvular heart disease, atrial fibrillation, hypertension, stroke, malignancy, arthritis, chronic pulmonary disease, Charlson comorbidity index (any points vs. no points), APS (continuous), 30-day Sickness at Admission Scale (quartiles), ASA status (1 or 2 points, 3 points, 4 or 5 points), smoking, malnourished or cachectic, preoperative transfusion. Model discrimination was excellent (C index = 0.85).