Table 1 The general form of a test-negative case–control study in the whole study population — patients who sought and those who did not seek medical care stratified by vaccination status. Note that we do not have any information about those who did not seek medical care (last two columns)
From: Correction of vaccine effectiveness derived from test-negative case–control studies
Vaccinated | Seeking Medical Care | Total | Not Seeking Medical Care | ||
|---|---|---|---|---|---|
Test + vea | Test –veb | Test + ve | Test –ve | ||
Yes | a | b | a + b | e | f |
No | c | d | c + d | g | h |
Total | a + c | b + d | n | e + g | f + h |