Designed experiments remain nearly always preferred to OFAT with many types and methods available,<ref>See [[:Category: Experimental design]], at bottom.</ref> in addition to fractional factorials which, though usually requiring more runs than OFAT, do address the three concerns above.<ref name=Czitrom>{{cite journal |last=Czitrom|first=Veronica|authorlink= Veronica Czitrom |year=1999 |title=One-Factor-at-a-Time Versus Designed Experiments |journal=American Statistician |volume=53 |issue=2 |pages=126–131 |doi=10.2307/2685731|jstor= 2685731}}</ref> One modern design over which OFAT has no advantage in number of runs is the [[Plackett-Burman design|Plackett-Burman]] which, by having all factors vary simultaneously (an important quality in experimental designs),<ref name=Czitrom /> gives generally [[Efficiency (statistics)|greater precision in effect estimation]].
