Given Hapunda

93 Figure 2: Post-test-Only Control-Group Design 3. Solomon Four-Group Design The Solomon four-group design is an experimental design that allows researchers to randomly assign participants to four groups, and then introduces the intervention or programme being evaluated to two of them. Thereafter, pre-testing and post-testing are conducted on one group that receives the intervention or programme and one that does not, and post-testing is conducted only on the other two groups. Advantages of the Solomon Four-Group Design The random assignment of subjects to four groups helps in assessing testing effects. The design is a combination of pretest-posttest control-group design and posttest-only control-group design (Rubin & Babbie, 2013). Disadvantages of the Solomon Four-Group Design The problem associated with this design is that it is not easy to find an adequate number of participants to assign randomly between two groups (the experimental and control groups) and four groups at large. Figure 3 below shows the Solomon Four-Group Design. Random Assignment Experimental group Post-test Control group Post-test Focus Box 6.: A Posttest-Only Control- Group Design The effectiveness of a self-help book and a personalised assessment feedback intervention was assessed by Cunningham (2002). He used a telephone survey to recruit participants who were later assigned to the self-help book only group, personalised feedback only group, a personalised feedback and self-help group, and a control group. The participants were followed after 6 months while comparing the differences in the groups. The group receiving the combined intervention reported a significant improvement in the drinking outcomes