Table 2 Example data extraction form with data extracted from bladder cancer Kaplan-Meier plot in Figure 1.
From: Practical methods for incorporating summary time-to-event data into meta-analysis
| Time at start of interval (months) | % Event-free on research | % Event-free on control | Reported numbers at risk on research | Reported numbers at risk on control |
|---|---|---|---|---|
| 0 | 100 | 100 | 491 | 485 |
| 3 | 97 | 97 | - | - |
| 6 | 92 | 92 | - | - |
| 9 | 86 | 84 | - | - |
| 12 | 78 | 75 | 372 | 355 |
| 15 | 73 | 70 | - | - |
| 18 | 68 | 63 | - | - |
| 21 | 65 | 60 | - | - |
| 24 | 62 | 58 | 283 | 257 |
| 27 | 60 | 56 | - | - |
| 30 | 58 | 54 | - | - |
| 33 | 56 | 52 | - | - |
| 36 | 54 | 51 | 200 | 187 |
| 42 | 52 | 49 | - | - |
| 48 | 51 | 46 | 139 | 132 |
| 54 | 49 | 44 | - | - |
| 60 | 49 | 43 | 93 | 80 |