Table 4.
Mean Knowledge Scores for each Time Delay after the Tutorial
| n | Score including all 20 items on each test | Score for the 3 malfunctioning items* | Final 17-item knowledge score | ||||
|---|---|---|---|---|---|---|---|
| Pretest | Posttest | Pretest | Posttest | Pretest | Posttest | ||
| Overall mean | 87 | 10.3 (0.2) | 12.4 (0.3) | 1.8 (0.1) | 1.6 (0.1) | 8.5 (0.2) | 10.8 (0.3) |
| Assigned delay | |||||||
| None | 14 | 9.6 (0.4) | 14.2 (0.6) | 1.9 (0.2) | 1.2 (0.2) | 7.8 (0.4) | 13.0 (0.5) |
| 1 day | 15 | 10.1 (0.6) | 12.7 (0.7) | 1.5 (0.1) | 1.5 (0.2) | 8.5 (0.6) | 11.2 (0.6) |
| 3 days | 15 | 9.6 (0.5) | 12.4 (0.6) | 1.7 (0.3) | 1.5 (0.2) | 7.8 (0.4) | 10.9 (0.5) |
| 8 days | 15 | 10.8 (0.5) | 12.8 (0.6) | 1.8 (0.1) | 1.8 (0.2) | 9.0 (0.4) | 11.0 (0.6) |
| 21 days | 14 | 10.4 (0.5) | 12.0 (0.9) | 1.6 (0.3) | 1.9 (0.3) | 8.8 (0.4) | 10.1 (0.7) |
| 55 days | 14 | 11.1 (0.6) | 10.2 (0.7) | 2.4 (0.2) | 1.7 (0.2) | 8.8 (0.6) | 8.5 (0.6) |
| P value† | .20 | .006 | .10 | .27 | .31 | <.0001 | |
Values are the mean (standard error) number of questions answered correctly for each category of knowledge items.
*Items for the learning objective were classified as malfunctioning if subjects were less likely to answer correctly after they completed the tutorial (at 0 or 1 day) than they were beforehand (on the pretest).
†Tests of significance are one-way ANOVA tests for differences between assignment groups on the pretest and the posttest.