Table 4.
The outcomes of the logistic and negative binomial components of the fitted ZINB regression model
| Logistic regression component | Negative binomial regression component | |||||
|---|---|---|---|---|---|---|
| Estimate ± Std. error | z value | Pr(>|z|)a | Estimate ± Std. error | z value | Pr(>|z|)a | |
| Intercept | 10.133 ± 0.449 | −22.545 | <.001 | −8.262 ± 0.240 | −34.376 | <.001 |
| Age | −0.025 ± 0.007 | −3.593 | <.001 | 0.004 ± 0.003 | 1.108 | 0.268 |
| Sex | ||||||
| Female | Reference category | |||||
| Male | −0.422 ± 0.176 | −2.403 | 0.016 | −0.122 ± 0.090 | −1.348 | 0.178 |
| Race | ||||||
| Caucasian | Reference category | |||||
| Asian/Pacific Islander | 1.335 ± 0.371 | 3.602 | <.001 | −0.391 ± 0.310 | −1.260 | 0.208 |
| Hispanic | −0.162 ± 0.529 | −0.307 | 0.759 | −0.273 ± 0.328 | −0.834 | 0.404 |
| African American | 0.542 ± 1.132 | 0.479 | 0.632 | −0.223 ± 0.642 | −0.347 | 0.728 |
| Other | 0.408 ± 0.517 | 0.789 | 0.430 | −0.058 ± 0.271 | −0.214 | 0.831 |
| BMI | ||||||
| Underweight | 0.081 ± 0.325 | 0.248 | 0.804 | −0.278 ± 0.179 | −1.551 | 0.121 |
| Normal | Reference category | |||||
| Overweight | 0.071 ± 0.257 | 0.278 | 0.781 | −0.384 ± 0.107 | −3.571 | <.001 |
| Obese | 0.864 ± 0.317 | 2.723 | 0.006 | −0.694 ± 0.168 | −4.119 | <.001 |
| Freq. of alcohol consumption | ||||||
| Never | Reference category | |||||
| Rarely | −0.802 ± 0.288 | −2.786 | 0.005 | −0.041 ± 0.134 | −0.306 | 0.759 |
| Occasionally | −0.661 ± 0.269 | −2.456 | 0.014 | −0.104 ± 0.138 | −0.754 | 0.451 |
| Regularly | −0.524 ± 0.287 | −1.825 | 0.068 | −0.212 ± 0.144 | −1.470 | 0.142 |
| Daily | −0.608 ± 0.343 | −1.774 | 0.076 | −0.208 ± 0.169 | −1.233 | 0.218 |
| Last exposure to antibiotics (days) | ||||||
| >365 | Reference category | |||||
| <365 | 0.648 ± 0.246 | 2.632 | 0.008 | −0.136 ± 0.125 | −1.084 | 0.278 |
| <180 | 1.687 ± 0.273 | 6.188 | <.001 | 0.115 ± 0.161 | 0.710 | 0.477 |
| <30 | 0.568 ± 0.469 | 1.212 | 0.226 | −0.105 ± 0.263 | −0.401 | 0.689 |
| <7 | 1.633 ± 0.519 | 3.149 | 0.002 | 0.334 ± 0.374 | 0.892 | 0.372 |
| Country of residence | ||||||
| USA | Reference category | |||||
| UK–Ireland | −2.802 ± 1.037 | −2.703 | 0.007 | 0.180 ± 0.113 | 1.590 | 0.112 |
| Europe Continental | −1.598 ± 1.380 | −1.158 | 0.247 | 0.258 ± 0.289 | 0.892 | 0.372 |
| Australia and NZL | −1.494 ± 0.982 | −1.522 | 0.128 | 0.148 ± 0.227 | 0.654 | 0.513 |
| Canada | −1.470 ± 0.931 | −1.578 | 0.115 | −0.150 ± 0.304 | −0.494 | 0.621 |
| Others | −2.299 ± 1.083 | −2.123 | 0.034 | 0.384 ± 0.580 | 0.661 | 0.509 |
| Drinking water source | ||||||
| City | Reference category | |||||
| Filtered | 0.094 ± 0.190 | 0.493 | 0.622 | −0.053 ± 0.094 | −0.558 | 0.577 |
| Bottled | −0.207 ± 0.393 | −0.527 | 0.598 | −0.020 ± 0.164 | −0.121 | 0.904 |
| Well | 0.407 ± 0.295 | 1.381 | 0.167 | 0.137 ± 0.167 | 0.822 | 0.411 |
| Level of education | ||||||
| ≤High school | 0.957 ± 0.441 | 2.170 | 0.030 | 0.226 ± 0.239 | 0.945 | 0.344 |
| College/bachelor’s | Reference category | |||||
| Graduate school | 0.176 ± 0.292 | 0.601 | 0.548 | 0.067 ± 0.111 | 0.602 | 0.547 |
| Dog | ||||||
| Absent | Reference category | |||||
| True | 0.270 ± 0.178 | 1.516 | 0.130 | −0.044 ± 0.094 | −0.469 | 0.639 |
| C-section | ||||||
| False | Reference category | |||||
| True | 0.209 ± 0.266 | 0.786 | 0.432 | 0.173 ± 0.151 | 1.143 | 0.253 |
| Vegetable frequency | ||||||
| <1 time/week | 0.102 ± 0.630 | 0.162 | 0.871 | −0.191 ± 0.330 | −0.580 | 0.562 |
| 1–2 times/week | 0.395 ± 0.399 | 0.991 | 0.322 | −0.099 ± 0.205 | −0.485 | 0.628 |
| 3–5 times/week | Reference category | |||||
| Daily | −0.216 ± 0.288 | −0.750 | 0.453 | 0.184 ± 0.114 | 1.618 | 0.106 |
| Thyroid condition | ||||||
| No condition | Reference category | |||||
| Diagnosed | −0.093 ± 0.431 | −0.216 | 0.829 | −0.394 ± 0.166 | −2.37 | 0.018 |
aStatistical significance in italics