NOECs na LOECs ni kuamua kwa hypothesis kupima (Dunnett ya mtihani, t mtihani na Bonferroni marekebisho, Steel ya wengi-moja Rank mtihani, au Wilcoxon Rank Sum mtihani na Bonferroni marekebisho), wakati LCs, ICs, na ECs ni kuamua kwa hatua makadirio mbinu (Probit uchambuzi, Spearman-Karber mbinu, Trimmed Spearman-Karber mbinu, Graphical mbinu au Linear Interpolation mbinu).
Uchunguzi wa nadharia ni jinsi LOECs hupatikana.