External validation of the discharge of hip fracture patients score.

Purpose: This paper reports the external validation of a recently developed instrument, the Discharge of Hip fracture Patients score (DHP) that predicts discharge location on admission in patients living in their own home prior to hip fracture surgery.

Methods: The DHP (maximum score 100 points) was applied to 125 hip fracture patients aged 50 or more years admitted to an academic centre in the northern part of The Netherlands (Groningen cohort). The characteristics of this cohort, sensitivity, specificity and positive and negative predictive value (PPV, NPV) of the DHP for discharge to an alternative location (DAL) were calculated and compared with the original cohort of hip fracture patients from the western part of The Netherlands (Delft cohort). Scoring 30 points or higher indicated DAL.

Results: The Groningen cohort was younger compared to the Delft cohort, (mean age 75.4 vs. 78.5 years, P = 0.005) but was more often classified ASA III/IV (46.4% vs. 25.2%, P < 0.001). Sensitivity of the DHP for DAL in the Groningen cohort was 75% (vs. 83.8%), specificity of 66.7% (vs. 64.7%) and a PPV of 86.3% (vs. 79.2%), compared to the Delft cohort.

Conclusion: External validation of the DHP was successful; it predicted discharge location of hip fracture patients accurately in another Dutch cohort, the sensitivity for DAL was somewhat lower but the PPV higher. Therefore, the DHP score is a useful valid and easily applied instrument for general hip fracture populations.