Experimental Research Designs

Below are some common research designs. Each has strengths and weaknesses. The rows within each design represent different groups. The columns represent the passage of time.

R=Random Assignment
X= Treatment
O=Observation (Assessment)






X O One Shot Case Study Design





O X O One-Group Pretest-Posttest Design





X O Static-Group Comparison Design
O





O X O Static-Group Pretest-Posttest Design
O O





R X O Randomized Posttest-Only, Control Group Design
R O





R O X O Randomized Pretest-Posttest Control Group Design
R O O





R O X O Ranomized Solomon Four-Group Design
R O O
R X O
R O





R = Random Assignment
X = Treatment
O = Observation (test or measurement of some type)

Del Siegle, Ph.D.
Neag School of Education – University of Connecticut
del.siegle@uconn.edu

www.delsiegle.com