Stone recurrence rates observed in the three time periods (see text for details)
| Recurrence rate (%) | ||||||||
|---|---|---|---|---|---|---|---|---|
| n | Recurrence | 5 y | 10 y | 15 y | RR | (95% CI) | p Value | |
| *RR, relative risk; CI, confidence interval. | ||||||||
| First period | 69 | 8 | 5.5 | 15.5 | 18.9 | 1 | ||
| Second period | 367 | 47 | 6.3 | 9.8 | 17.7 | 1.11 | (0.52–2.35) | 0.79 |
| Third period | 547 | 56 | 10.1 | 14.3 | — | 1.51 | (0.71–3.22) | 0.29 |