Table 3. Observed and predicted results of cross-validation and external validation.
| Validation by rounds of screens and detection methods | Observed number | Expected number |
|---|---|---|
|
Cross-validation | ||
|
1st round of screen (prevalence screen) | ||
| Free of breast cancer | 333 081 | 333 082.7 |
| Screen-detected cases |
737 |
735.3 |
|
2nd round of screen (subsequent screen) | ||
| Free of breast cancer | 332 349 | 332 360 |
| Screen-detected cases | 463 | 458.67 |
| Interval cancers |
269 |
262.3 |
|
3rd round of screen (subsequent screen) | ||
| Free of breast cancer | 331 624 | 331 587.9 |
| Screen-detected cases | 496 | 484.19 |
| Interval cancers |
229 |
276.93 |
Goodness of fit test:  | ||
|
External validation | ||
|
Prevalence screen | ||
| Free of breast cancer | 4,791 | 4,802.66 |
| Screen-detected cases |
76 |
64.34 |
|
Subsequent screen | ||
| Free of breast cancer | 3,700 | 3,676.75 |
| Screen-detected cases | 11 | 18.29 |
| Interval cancers |
7 |
6.19 |
Goodness of fit test: 
| ||