Understanding how comprehensive geriatric assessment works: the importance of varied methodological approaches.

Comprehensive geriatric assessment (CGA) is the gold standard model of care for older adults with frailty. However, despite a large number of published clinical trials, there remain many unanswered questions about how CGA works in different circumstances. This uncertainty stems from CGA being a deeply complex intervention that is heavily modified by context. This review describes recent and novel methodological approaches that explore the active ingredients of CGA and their interaction with context. Future research should continue to embrace broad methodologies that can help us better understand this intervention, in such a way that it can be implemented with fidelity and associated with positive outcomes for older adults.