{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,24]],"date-time":"2026-09-24T00:22:25Z","timestamp":1790209345588,"version":"4.1.0"},"reference-count":57,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2021,7,27]],"date-time":"2021-07-27T00:00:00Z","timestamp":1627344000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPM"],"abstract":"<jats:p>Postoperative death within 1 year following hip fracture surgery is reported to be up to 27%. In the current study, we benchmarked the predictive precision and accuracy of the algorithms support vector machine (SVM), na\u00efve Bayes classifier (NB), and random forest classifier (RF) against logistic regression (LR) in predicting 1-year postoperative mortality in hip fracture patients as well as assessed the relative importance of the variables included in the LR model. All adult patients who underwent primary emergency hip fracture surgery in Sweden, between 1 January 2008 and 31 December 2017 were included in the study. Patients with pathological fractures and non-operatively managed hip fractures, as well as those who died within 30 days after surgery, were excluded from the analysis. A LR model with an elastic net regularization were fitted and compared to NB, SVM, and RF. The relative importance of the variables in the LR model was then evaluated using the permutation importance. The LR model including all the variables demonstrated an acceptable predictive ability on both the training and test datasets for predicting one-year postoperative mortality (Area under the curve (AUC) = 0.74 and 0.74 respectively). NB, SVM, and RF tended to over-predict the mortality, particularly NB and SVM algorithms. In contrast, LR only over-predicted mortality when the predicted probability of mortality was larger than 0.7. The LR algorithm outperformed the other three algorithms in predicting 1-year postoperative mortality in hip fracture patients. The most important predictors of 1-year mortality were the presence of a metastatic carcinoma, American Society of Anesthesiologists(ASA) classification, sex, Charlson Comorbidity Index (CCI) \u2264 4, age, dementia, congestive heart failure, hypertension, surgery using pins\/screws, and chronic kidney disease.<\/jats:p>","DOI":"10.3390\/jpm11080727","type":"journal-article","created":{"date-parts":[[2021,7,27]],"date-time":"2021-07-27T12:18:31Z","timestamp":1627388311000},"page":"727","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":40,"title":["Predicting 1-Year Mortality after Hip Fracture Surgery: An Evaluation of Multiple Machine Learning Approaches"],"prefix":"10.3390","volume":"11","author":[{"given":"Maximilian Peter","family":"Forssten","sequence":"first","affiliation":[{"name":"Department of Orthopedic Surgery, Orebro University Hospital, 701 85 Orebro, Sweden"},{"name":"School of Medical Sciences, Orebro University, 702 81 Orebro, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1918-9443","authenticated-orcid":false,"given":"Gary Alan","family":"Bass","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Orebro University, 702 81 Orebro, Sweden"},{"name":"Division of Traumatology, Emergency Surgery and Surgical Critical Care, University of Pennsylvania, Philadelphia, PA 19104, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ahmad Mohammad","family":"Ismail","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Orebro University Hospital, 701 85 Orebro, Sweden"},{"name":"School of Medical Sciences, Orebro University, 702 81 Orebro, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shahin","family":"Mohseni","sequence":"additional","affiliation":[{"name":"School of Medical Sciences, Orebro University, 702 81 Orebro, Sweden"},{"name":"Division of Trauma and Emergency Surgery, Department of Surgery, Orebro University Hospital, 701 85 Orebro, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3552-9153","authenticated-orcid":false,"given":"Yang","family":"Cao","sequence":"additional","affiliation":[{"name":"Clinical Epidemiology and Biostatistics, School of Medical Sciences, Orebro University, 702 81 Orebro, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Forssten, M.P., Mohammad Ismail, A., Sjolin, G., Ahl, R., Wretenberg, P., Borg, T., and Mohseni, S. 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