  Starobinsky described an inflationary scenario in which quantum corrections
to vacuum Einstein equations drive the inflation. The quantum cosmology of the
model is studied by solving the Wheeler-DeWitt equation. A connection between
uncertainty requirement, randomness in initial states and curvature fluctuation
is studied with a Schr\"{o}dinger-type equation through a time parameter
prescription. The result obtained is applied to understand the decoherence
mechanism in quantum gravity in the Starobinsky description.
