Table 1.
Demographic characteristics of the study population, by cases with self-reported gastroenteritis, non-cases and the uncertain group, during the Campylobacter outbreak in Askøy
| All | Cases | Non-cases | Uncertain | x2 | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | n | % | pa | ||
| Total | 3624 | 100 | 749 | 20.7* | 2417 | 66.7* | 458 | 12.6* | ||
| Sex | 0.174 | |||||||||
| Male | 1243 | 34.3 | 291 | 38.9 | 822 | 34.0 | 130 | 28.4 | ||
| Female | 1957 | 54.0 | 405 | 54.1 | 1291 | 53.4 | 261 | 57.0 | ||
| Missing | 424 | 11.7 | 53 | 7.1 | 304 | 12.6 | 67 | 14.6 | ||
| Age range (years) | 1–91 | 1–82 | 1–91 | 1–81 | ||||||
| Age | < 0.01 | |||||||||
| 0–4 | 22 | 0.6 | 6 | 0.8 | 12 | 0.5 | 4 | 0.9 | ||
| 5–14 | 30 | 0.8 | 8 | 1.1 | 14 | 0.6 | 8 | 1.7 | ||
| 15–24 | 236 | 6.5 | 72 | 9.6 | 136 | 5.6 | 28 | 6.1 | ||
| 25–34 | 483 | 13.3 | 112 | 15.0 | 296 | 12.2 | 75 | 16.4 | ||
| 35–44 | 701 | 19.3 | 159 | 21.2 | 460 | 19.0 | 82 | 17.9 | ||
| 45–54 | 691 | 19.1 | 171 | 22.8 | 427 | 17.7 | 93 | 20.3 | ||
| 55–64 | 477 | 13.2 | 101 | 13.5 | 328 | 13.6 | 48 | 10.5 | ||
| 65–74 | 445 | 12.3 | 52 | 6.9 | 349 | 14.4 | 44 | 9.6 | ||
| 75–84 | 82 | 2.3 | 10 | 1.3 | 67 | 2.8 | 5 | 1.1 | ||
| ≥ 85 | 2 | 0.1 | 0 | 0.0 | 2 | 0.1 | 0 | 0.0 | ||
| Missing | 455 | 12.6 | 58 | 7.7 | 326 | 13.5 | 71 | 15.5 | ||
| Education level** | < 0.01 | |||||||||
| Elementary school | 175 | 4.9 | 47 | 6.4 | 102 | 4.3 | 26 | 5.9 | ||
| High school | 1192 | 33.6 | 299 | 40.9 | 748 | 31.5 | 145 | 32.7 | ||
| University/college | 1431 | 40.4 | 290 | 39.7 | 981 | 41.4 | 160 | 36.0 | ||
| Missing | 748 | 21.1 | 95 | 13.0 | 540 | 22.8 | 113 | 25.5 | ||
| Employment** | < 0.01 | |||||||||
| Student/pupil | 146 | 4.1 | 34 | 4.7 | 95 | 4.0 | 17 | 3.8 | ||
| Worker | 1879 | 53.0 | 459 | 62.8 | 1193 | 50.3 | 227 | 51.1 | ||
| Self-employed | 94 | 2.7 | 20 | 2.7 | 62 | 2.6 | 12 | 2.7 | ||
| Unemployed | 89 | 2.5 | 22 | 3.0 | 52 | 2.2 | 15 | 3.4 | ||
| On welfare | 177 | 5.0 | 55 | 7.5 | 95 | 4.0 | 27 | 6.1 | ||
| Pensioner | 423 | 11.9 | 50 | 6.8 | 336 | 14.2 | 37 | 8.3 | ||
| Missing | 738 | 20.8 | 91 | 12.4 | 538 | 22.7 | 109 | 24.5 | ||
| Houshold income | 0.28 | |||||||||
| < 250,000 | 86 | 2.4 | 23 | 3.1 | 51 | 2.1 | 12 | 2.6 | ||
| 250,000–499,999 | 393 | 10.8 | 89 | 11.9 | 254 | 10.5 | 50 | 10.9 | ||
| 500,000–749,999 | 609 | 16.8 | 130 | 17.4 | 388 | 16.1 | 91 | 19.9 | ||
| 750,000–1,000,000 | 683 | 18.8 | 171 | 22.8 | 437 | 18.1 | 75 | 16.4 | ||
| > 1,000,000 | 900 | 24.8 | 191 | 25.5 | 621 | 25.7 | 88 | 19.2 | ||
| missing | 953 | 26.3 | 145 | 19.4 | 666 | 27.6 | 142 | 31.0 | ||
| Marital status** | < 0.01 | |||||||||
| Single | 440 | 12.4 | 131 | 17.9 | 251 | 10.6 | 58 | 13.1 | ||
| Married/cohabitant | 2152 | 60.7 | 459 | 62.8 | 1446 | 61.0 | 247 | 55.6 | ||
| Divorced/separated | 153 | 4.3 | 40 | 5.5 | 93 | 3.9 | 20 | 4.5 | ||
| Widow/widower | 61 | 1.7 | 9 | 1.2 | 45 | 1.9 | 7 | 1.6 | ||
| Missing | 740 | 20.9 | 92 | 12.6 | 536 | 22.6 | 112 | 25.2 | ||
Distribution within characteristics is given by column unless stated by *
*Distribution by row, i.e., within study population
**Analyses restricted to participants ≥ 18 years
aP values from Pearson’s x2-test of association calculated from cross tables not including missing values and ‘uncertain group’