Table 3.
Summary of estimates for key group differences before and after matching
| Comparison | Posttest difference (t1) |
Follow-up difference (t2) |
Fadeout effect (t1-t2) |
Matched follow-up difference (m2) |
Proportion of fadeout explained by m2 |
|---|---|---|---|---|---|
| Treatment vs. Control | 0.41 | 0.12 | 0.29 | 0.21 | 0.72 |
| Follow-through vs. Control | 0.39 | 0.17 | 0.22 | 0.16 | 0.73 |
| Higher-achieving treatment vs. Control | 0.40 | 0.14 | 0.26 | 0.24 | 0.92 |
| Lower-achieving treatment vs. Control | 0.42 | 0.16 | 0.26 | 0.16 | 0.62 |
Note. Values can be re-calculated by hand from Tables 1 and 2, and Appendix Tables F–I. Variable names (t1, t2, and m2) and formulae used to calculate them correspond to those shown in Figure 2.