Fig. 1.

Rectangularization of survival curves. Hypothetical survival curves with different degrees of ‘rectangularization’ (as indicated by the red arrow): increasing ‘rectangularization’ implies a high, constant probability of survival to a very advanced age (i.e., a long ‘shoulder’ of the curve) and a marked compression of morbidity and death into a very narrow age range (i.e., an almost vertical drop in survival at the end of life)