| 2020 | 2022 | |||||||
| Sample | Cases | Controls | Student test | Sample | Cases | Controls | Student test | |
| Number of observations | 228 | 76 | 152 | 224 | 74 | 150 | ||
| Middle age | 37 | 36 | 37 | t = −1.623; p = 0.106 | 38 | 37 | 38 | t = −0.978; p = 0.329 |
| Standard deviation | 7 | 8 | 7 | 7 | 8 | 7 | ||