Table 2.
Calculations of the 95% CI for a hypothetical vaccinated population of 3 million (NP)
| Risk group | D = NP –(N1 + N2) | D1 = D × f | D2 = D × (1 − f) | LN(OR) | SELN(OR) | 95% CI = e(LN[OR] ± 1.96 × SELN[OR]) | ||||
|---|---|---|---|---|---|---|---|---|---|---|
| Men ≥ 56 | 2,999,936 | 183,596 | 2,816,340 | 2.4 | 0.25 | 6.4–17 | ||||
| Women 19–34 | 2,999,936 | 275,236 | 2,701,200 | 1.0 | 0.30 | 1.6–4.9 | ||||
| Autoimmune disease | 2,999,936 | 89,998 | 2,909,938 | 1.8 | 0.34 | 3.0–12 | ||||
| Thymectomy for thymoma | 2,999,977 | 4 | 2,999,973 | 12 | 0.72 | 34,000–580,000 | ||||
| SLE | 2,999,936 | 3,600 | 2,996,336 | 3.7 | 0.59 | 13–130 | ||||
| Pernicious anemia | 2,999,936 | 47,399 | 2,952,537 | 0.010 | 1.0 | 0.14–7.1 | ||||
D = total number exposed who did not become ill; NP = total number of exposed subjects; D1 = number of exposed subjects with the risk factor who remained well; D2 = number of exposed subjects without the risk factor who remained well; SELN(OR) = standard error of the natural logarithm of the odds ratio; CI = confidence interval; LN = natural logarithm; N1 = the number of subjects with the risk factor who became ill; N2 = the number of subjects without the risk factor who became ill; f = frequency of the suspected risk factor; and OR = odds ratio.