Table 2.
Summary of the post hoc one-way ANOVA and Tukey’s HSD post hoc results to explore the significant interaction between group and block in reward learning, with group as the between-subject variable, and the percentage of correct responses on a each one of the four reward learning block was the within-subject variable, with a Bonferroni correction adjusted α = 0.0125 to protect the level of significance.
| Statistical test | Within-subject variable | Between-subject variable | df-1 | df-2 | F | p | η2 |
|---|---|---|---|---|---|---|---|
| One-way ANOVA | Block 1 reward | Group (MDD, MDD-T, HC) | 2 | 50 | 1.571 | 0.218 | – |
| One-way ANOVA | Block 2 reward | Group (MDD, MDD-T, HC) | 2 | 50 | 3.862 | 0.28 | – |
| One-way ANOVA | Block 3 reward | Group (MDD, MDD-T, HC) | 2 | 50 | 4.973 | 0.011* | 0.166 |
| Tukey’s HSD | HC vs. MDD-T | – | – | – | 0.04* | – | |
| HC vs. MDD | – | – | – | 0.097 | – | ||
| MDD vs. MDD-T | – | – | – | 0.827 | – | ||
| One-way ANOVA | Block 4 reward | Group (MDD, MDD-T, HC) | 2 | 50 | 6.038 | 0.004* | 0.194 |
| Tukey’s HSD | HC vs. MDD | – | – | – | 0.006* | – | |
| HC vs. MDD-T | – | – | – | 0.049* | – | ||
| MDD vs. MDD-T | – | – | – | 0.572 | – |
HC, healthy controls; MDD, medication-naïve patients with MDD; MDD-T, SSRI-treated patients with MDD. The symbol “*” marks significant results.