Table 2. Main results and validity of the screening.
| Item | Wave 1 | Wave 2 |
|---|---|---|
| N invited | 8705 | 6769 |
| N screened | 6828 | 5046 |
| % non-response/attrition | 22% | 25% |
| Screening results | ||
| % sent to endoscopy – total | 34% | 20% |
| Because cancer suspect | 3% | 2% |
| With other pathologies | 31% | 18% |
| Stomach cancer cases | ||
| N detected | 59 | 28 |
| N undetected | 6 | 4 |
| Cancer detected at early stage | 55% | 80% |
| X-ray validity indicators a | ||
| Sensitivity | 91% | 88% |
| Specificity | 67% | 80% |
| Positive predictive value | 3% | 3% |
| Hypothetical restrictedb screening | ||
| Sensitivity | 58% | 47% |
| Specificity | 98% | 98% |
| Positive predictive value | 19% | 16% |
a
All sent to endoscopy are taken as positives.
b
If only cancer suspicious participants were sent to endoscopy.