The Pretest-Posttest Design With No Control Group

    This design has such serious problems that Campbell & Stanley (1963) labeled it as "pre-experimental."  There are lots of web documents out there discuss the problems with this design.  I list a few of them here.

• An Introduction to Research Design -- see the section "Threats to the Internal Validity of the One Group Pretest-Posttest Design."
• Why Is the One-Group Pretest–Posttest Design Still Used?
• One Group Pretest-Posttest Design
• One Group Designs
• Pretest-Posttest Statistical Analysis -- No Control Group

Campbell DT, Stanley JC. Experimental and Quasi-Experimental Designs for Research. Wadsworth; 1963 -- recommended reading

My Design Lessons Page.

Karl L. Wuensch, November, 2022.