Table 6 Robust Poisson regression models estimating prevalence ratio (PR) and 95% confidence interval (CI) to evaluate the association of various independent variables on the GERD
Variable | Crude model | Adjusted model | ||
|---|---|---|---|---|
PR (95% CI) | P value | PR (95% CI) | P value | |
Cigarette smoking | < 0.001 |  | < 0.001 | |
 Yes | 1.132 (1.082–1.186) | 1.139 (1.089–1.192) | ||
 No | 1.0 | 1.0 | ||
Body mass indexa | < 0.001 |  | < 0.001 | |
 Overweight range and obese | 1.066 (1.033–1.100) | 1.060 (1.027–1.093) | ||
 Normal and under-weight | 1.0 | 1.0 | ||
Hiatus hernia | < 0.001 |  | < 0.001 | |
 Yes | 1.175 (1.129–1.223) | 1.140 (1.095–1.188) | ||
 No | 1.0 | 1.0 | ||
Gastric ulcer | < 0.001 |  | 0.001 | |
 Yes | 0.897 (0.826–0.973) | 0.875 (0.809–0.947) | ||
 No | 1.0 | 1.0 | ||
Duodenal ulcer | 0.004 | Â | 0.001 | |
 Yes | 0.919 (0.867–0.974) | 0.911 (0.862–0.963) | ||
 No | 1.0 | 1.0 | ||
Age | 1.002 (1.001–1.003) | 0.001 | 1.002 (1.001–1.003) | < 0.001 |
Sociodemographic status | 0.211 | Â | 0.064 | |
 Rural | 1.021 (0.988–1.055) | 1.030 (0.998–1.063) | ||
 Urban | 1.0 | 1.0 | ||
Helicobacter pylori | 0.106 | Â | 0.158 | |
 Positive | 1.030 (0.994–1.068) | 1.026 (0.990–1.064) | ||
 Negative | 1.0 | 1.0 | ||