Computer-implemented methods for inspecting and/or classifying a wafer are provided. One computer-implemented includes detecting defects on a wafer using one or more defect detection parameters, which are determined based on a non-spatially localized characteristic of the wafer that is determined using output responsive to light scattered from the wafer generated by an inspection system. Another computer-implemented method includes classifying a wafer based on a combination of a non-spatially localized characteristic of the wafer determined using output responsive to light scattered from the wafer generated by an inspection system and a spatially localized characteristic of the wafer determined using the output.