As compared to a routine case control study, nested case control study avoids problems (in study design) related to -
A nested case-control (NCC) study is a variation of a case-control study in which cases and controls are drawn from the population in a fully enumerated coho. Usually, the exposure of interest is only measured among the cases and the selected controls. Thus the nested case-control study is more efficient than the full coho design.
Temporal association
Confounding bias
Need for long follow up
Randomization
Epidemiology