| Date |
| ||||
| before OP (n = 458) | after OP (n = 458) | Difference | |||
Variable | mean | s.d. | mean | s.d. | mean | s.d. |
CIRC | 24.29 | 1.31 | 23.24 | 1.25 | 1.05 | 0.51 |