Designs Isolating Testing Effects: Cross-Over, Solomon Four-Fold, and More

Cross-over and Solomon four-fold designs are known to isolate testing effects. These designs are employed to control for the influence of pre-test measurements on the results of an experiment.

'Cross-over' designs involve switching participants between treatment groups over time, allowing for the measurement of the effect of both treatment and control conditions within the same individuals. This design helps mitigate the influence of testing effects by ensuring participants experience both conditions.

The 'Solomon four-fold' design is a more complex design that includes two control groups and two treatment groups. One control group and one treatment group receive a pre-test, while the other control group and treatment group do not. This design allows researchers to isolate the effects of testing, treatment, and the interaction between the two.

By implementing these designs, researchers can gain a more accurate understanding of the true effects of their intervention and reduce the bias caused by pre-test sensitization.