Simple slopes for significant interactions between study design features and participation appraisals predicting estimated participation likelihood
| Interest | Enjoyment | Contribution | ||||
| b | SE | b | SE | b | SE | |
| Study duration | ||||||
| 3 days | 2.45*** | 0.48 | 2.51*** | (0.46) | 1.96*** | 0.64 |
| 21 days | 5.40*** | 0.41 | 5.00*** | (0.42) | 6.28*** | 0.56 |
| Prompt frequency | ||||||
| 3 × day | 2.88*** | 0.46 | 2.35*** | 0.44 | – | – |
| 9 × day | 5.23*** | 0.44 | 5.41*** | 0.44 | – | – |
| Prompt length | ||||||
| 1 min per prompt | 3.11*** | 0.48 | 2.71*** | 0.45 | 3.02*** | 0.65 |
| 5 min per prompt | 4.92*** | 0.43 | 4.95*** | 0.43 | 5.45*** | 0.57 |
***P<0.001. There were no significant interactions for compensation or study effort; we did not examine simple slopes for non-significant interactions.