In a design, half the participants receive only a posttest, while the other half receives both a pretest and a posttest. pretest-posttest one-group pretest-posttest Solomon four-group two-group pretest-posttest

Solomon four-group

Explanation:

In a Solomon four-group design, half the participants receive only a posttest, while the other half receives both a pretest and a posttest.

Solomon four-group was developed by Richard Solomon , this design is a standard pretest-posttest two-group design and the posttest only control design, it assesses the effect of having been pretested on the magnitude of the treatment effect and design involves individuals being randomized into four groups: two treatment groups and two control groups