Frailty: the great confounder, the great forgotten

To the Editor: Ryan et al 1 present the results of SAFE PACE-2, which are at odds with SAFE PACE-1.2 The authors discuss that this may be due to greater frailty in SAFE PACE-2 participants. This point is valid and merits further reflection in relation to recent frailty literature. Frailty is a well-recognised clinical syndrome, it but remains difficult to define and measure. Central to the concept of frailty is …