Comparison of a frailty short interview to a validated frailty index in adults hospitalized for acute respiratory illness.

Background: Frailty is an important physiologic factor in studies of influenza and influenza vaccines carried out in older adults and hospitalized populations. Unfortunately, comprehensive assessments of frailty requiring physical assessments and extensive medical record review are not often feasible in time- and resource-limited settings common to studies of influenza and influenza vaccines.

Methods: We developed a 5-question frailty short interview, and implemented it in a multicenter, hospital-based study of influenza over two years.