We propose an improved statistical approach for modeling interconnect slew that takes into account the scattering effect of a nanoscale wire. We first propose a simple, closed-form scattering effect resistivity model, considering the effects of both width and thickness. Then we use this model to derive statistical expressions of the slew metrics using the SS2M model. We find that the delay and slew can be greatly increased when considering the scattering effect. The proposed statistical SS2M model has an average error of 4.16% with respect to SPICE Monte Carlo simulations, with an average error of standard deviation of only 3.06%.