An Independent Study Verifies The Results
Conducted Every 2 Years by:
John B. Watson, Ph.D. and the staff of
San Diego, California.
The statistical results show a positive treatment effect across all grades analyzed. The improvement in mean scores between pre and post-tests across all grades analyzed ranges from 14.9 to 24.3. The students performed significantly better on a math posttest after receiving instruction through the Learning Center (refer to Figure 2).
While these results show a positive treatment effect, there are a number of threats to the statistical results. The study is not experimental in design, and could benefit from a more controlled environment. This research is designed to supplement other studies to determine the effectiveness of the learning center. This design has inherent limitations, namely participants may improve over time without intervention of any kind, and these changes can be mistakenly attributed to the program under evaluation. This design could not indicate whether the program solely caused improvement in participants; as there is no way to distinguish between changes over time due to other factors and effects specific to the program. As a single group design, this study was easier to implement and less expensive study than experimental design, but did not include a control group, which could isolate the treatment effect and bias.