Social scientists have found it helpful to split validity into four main types: statistical conclusion validity, internal validity, construct validity, and external validity (Shadish, Cook, and Campbell 2001, Ch 2).
Ososayensi bezenhlalo baye bakuthola kuwusizo ukuqhekeza kwemukeleka zibe izinhlobo ezine eziyinhloko: kwezibalo isiphetho kwemukeleka, kwemukeleka yangaphakathi, ukwakha kwemukeleka, nobuqiniso yangaphandle (Shadish, Cook, and Campbell 2001, Ch 2).