Successful aging and frailty: mutually exclusive paradigms or two ends of a shared continuum?

The conceptualization of positive and negative states of aging is contentious at the inter- and intraparadigm level; lack of consensus exists within and between states. Working within their respective paradigms, successful aging and frailty researchers may have lost sight of the larger picture. Are successful aging researchers describing nonfrail individuals? Are frailty researchers describing unsuccessful aging? It is imperative that researchers are cognizant of the ways in which their perspectives are contextualized within the literature and within related paradigms, so as to be able to clearly communicate their research and to ensure they are working within the appropriate paradigm to facilitate desired outcomes. Here we discuss the similarities and differences between successful aging and frailty in terms of the scope and emphasis of their constituent components and functioning: both SA and frailty include biomedical components; SA examines the high end, whilst frailty predominately examines the low end of the functioning spectrum. Frailty models emphasize the biomedical realm, whilst SA models emphasize both the biomedical and the psychosocial.