WDesign of experiments
WBetween-group design
WCase–control study
WClinical trial
WConfounding
WCooperative pulling paradigm
WData collection
WData dredging
WDependent and independent variables
WDrug design
WExperiment
WFactorial experiment
WField experiment
WGroup testing
WInteraction (statistics)
WLady tasting tea
WLatin square
WOptimal design
WParadigm (experimental)
WPlacebo-controlled study
WQuasi-experiment
WRandomized controlled trial
WRandomized experiment
WResponse surface methodology
WSteiner system
WStock sampling
WUp-and-Down Designs
WVaccine trial