METHODS: This is a validation study of a new frailty assessment that can be administered by outpatient care nurses. The nurse directed frailty assessment (NDFA) encompasses the medical, psychological, social, and functional domain, based on standard care, and can be performed without any specialised equipment. Performance of the NDFA is compared to a comprehensive geriatric assessment (CGA)-based frailty index (FI), with generalised linear model with reporting of hazard ratios (HR) and 95% confidence intervals (95% CI). The best cutoff value for the NDFA was assessed by Youden index and the area under the receiver operator curve (ROC). RESULTS: Within 1 year, 15 patients (5%) died, 57 (18%) had an unplanned hospital admission, and 83 (26%) visited the emergency department (ED). Based on the Youden index and ROC curve, the best cutoff value for the NDFA was 4 points. With a binary logistic regression model, an HR of 3.59 (95% CI 1.16-11.15, p <
0.001) was found for mortality. In the general mixed model with Poisson logistic regression, an HR of 1.78 (95% CI 1.06-2.97, p 0.028) was found for unplanned hospital and an HR of 1.87 (95% CI 1.25-2.78, p 0.002) was found for ED visits. The HR and 95% CI of the FI were similar for all three outcome measures. CONCLUSIONS: The NDFA identifies patients at risk for hospitalisation, emergency department visits, and mortality within 12 months equally well as the FI. Further research is necessary to determine the effectiveness of the NDFA in other settings than the geriatric medicine outpatient population.