Cesari M, et al. - Researchers in this study designed and introduced a Frailty Index (FI; according to the age-related accumulation of deficit model) in a large cohort of hospitalized older persons, in order to benefit from its capacity to comprehensively weight the risk profile of the individual. From 2010 to 2016, patients aged 65 and older recruited in the REPOSI register were considered in the present analyses. For negative outcomes, FI confirmed its strong predictive value. The findings suggested that implementation of FI in cohort studies (including those conducted in the hospital setting) could provide valuable information for better weighting the complexity of the older person and accordingly design personalized interventions.