This study shows that the extent of floodplain inundation is a function of the peak-flow coefficient of variation but that the frequency of floodplain inundation primarily depends on the amount of channel adjustment permitted annually (i.e. changes in channel width, depth and slope).

http://onlinelibrary.wiley.com/doi/10.1002/2016WR020277/abstract;jsessionid=209B62DA8C2DF462F8FF51908AC923DB.f03t01