Validity of Nottingham Hip Fracture Score in Different Health Systems and a New Modified Version Validated to the Greek Population

BACKGROUND The Nottingham Hip Fracture Score (NHFS) is validated as a predictive mortality tool in patients with hip fracture. However, it has not been modified or validated widely other than in the UK NHS health systems. MATERIAL AND METHODS We assessed the predictive capability of the NHFS for 30-day mortality after surgery for hip fracture in the Greek population and then compared the original model to a modified one. We applied the NHFS to the Greek population and created a modified model of the NHFS by including the New Mobility Score (NMS) (Parker and Palmer, 1993) to the evaluated parameters and excluding the parameter of institution. We ran a prospective study over a period of 3 years in our institution, collecting full data from 349 patients. All data were analyzed using SPSS, version 20. RESULTS From all 349 patients, with a mean age of 80.82 years, only 85 (24.4%) were men. All patients were followed up for at least 30 days and the NHFS and modified NHFS prediction were compared with the mortality rate of patients. The area under the ROC curve for both models suggested acceptable accuracy (original NHFS 0.83, modified NHFS 0.84). Calibration was acceptable for both models (Hosmer-Lemeshow p=0.31 and 0.11, respectively). CONCLUSIONS Both the original and the modified NHFS were significant predictors of 30-day mortality. A higher-power study might be able to show superiority of the modified one for the Greek population in the future.