FIM Motor Scores for Classifying Community Discharge After Inpatient Rehabilitation for Hip Fracture

ObjectiveTo assess the utility of functional status in classifying patients by discharge setting after inpatient rehabilitation for hip fracture.DesignRetrospective cohort study.SettingA total of 1257 inpatient rehabilitation facilities in the United States.PatientsMedicare beneficiaries (N = 117,168) receiving inpatient rehabilitation for hip fracture from 2007 to 2009.MethodsReceiver operating characteristic curve analyses to assess the overall discriminatory ability of functional status scores (Functional Independence Measure [FIM] total, FIM cognition, and FIM motor) and to identify the functioning threshold that best differentiates patients by discharge setting.Main Outcome MeasurementsDischarge setting (community versus institutional).ResultsApproximately 68% of patients were discharged to the community after inpatient rehabilitation for hip fracture. Receiver operating characteristic curve analyses indicate that discharge FIM motor ratings (area under the curve: 0.84) alone are as effective as a multivariable model (area under the curve: 0.85), including sociodemographic and clinical factors, in discriminating patients discharged to the community from those discharged to an institution. A discharge FIM motor rating of 58 yielded the best balance in sensitivity and specificity for classifying patients by discharge setting.ConclusionsDischarge FIM motor ratings demonstrated good discriminatory ability for classifying discharge setting. An FIM motor rating of 58 may serve as a clinical tool to guide treatment plans and/or as additional information in complex discharge planning decisions for patients with hip fracture.