Missing data patterns in CDAI example data
| Pattern | 12 weeks | 24 weeks | 36 weeks | 44 weeks | 52 weeks | Frequency (%) |
| 1 | X | X | X | X | X | 204 (73) |
| 2 | X | X | X | X | O | 2 (0.72) |
| 3 | X | X | X | O | X | 3 (1.08) |
| 4 | X | X | X | O | O | 4 (1.43) |
| 5 | X | X | O | O | O | 8 (2.87) |
| 6 | X | O | X | X | X | 1 (0.36) |
| 7 | X | O | X | O | X | 1 (0.36) |
| 8 | X | O | O | O | O | 31 (11.11) |
| 9 | O | X | X | X | X | 1 (0.36) |
| 10 | O | O | O | O | O | 24 (8.60) |
CDAI, Collective Data Analysis Initiative Database; O, missing; X, observed.