Table 4.
Univariate and multivariate analysis of factors associated with seropositivity, adjusted for clustering effects of time periods
| Demographics | Categories | Univariate odds ratio (OR) (95 % confidence interval) | p-value | Multivariate (adjusted) OR (95% confidence interval) | p-value |
|---|---|---|---|---|---|
| Subpopulation | Rural | (ref) | (ref) | ||
| Urban slum | 1.95 (1.52–2.49) | < 0.001 | 2.01 (1.57–2.59) | < 0.001 | |
| Urban affluent | 1.51 (1.17–1.95) | 0.002 | 0.95 (0.65–1.39) | 0.786 | |
| Healthcare workers | 2.13 (1.64–2.78) | < 0.001 | 1.472 (0.93–2.33) | 0.099 | |
| Age a | < 20 years | (ref) | |||
| 21–40 years | 1.13 (0.88–1.45) | 0.342 | |||
| 41–60 years | 1.10 (0.84–1.44) | 0.482 | |||
| > 60 years | 0.93 (0.66–1.31) | 0.695 | |||
| Gender a | Male | (ref) | |||
| Female | 1.14 (0.95–1.36) | 0.163 | |||
| Education | Graduate | (ref) | |||
| Primary to high school* | 0.76 (0.63–0.93) | 0.006 | 0.92 (0.66–1.29) | 0.641 | |
| Illiterate | 0.62 (0.44–0.89) | 0.009 | 0.77 (0.48–1.25) | 0.295 | |
| Occupation | Professional | (ref) | (ref) | ||
| Semi-professional | 1.13 (0.79–1.60) | 0.516 | 0.85 (0.53–1.36) | 0.496 | |
| Skilled worker | 0.70 (0.53–0.93) | 0.012 | 0.72 (0.42–1.23) | 0.223 | |
| Unskilled/daily wage laborer | 0.69 (0.47–1.04) | 0.074 | 0.81 (0.43–1.53) | 0.510 | |
| Housewife/unemployed/student | 1.81 (0.64–1.03) | 0.089 | 0.86 (0.51–1.47) | 0.584 | |
| Socioeconomic class | Upper | (ref) | (ref) | ||
| Middle | 1.39 (1.05–1.86) | 0.024 | 1.77 (1.17–2.67) | 0.007 | |
| Lower | 0.90 (0.68–1.19) | 0.471 | 1.04 (0.59–1.83) | 0.900 | |
| Smoking habita | Smoker | 1.25 (0.64–2.45) | 0.509 | ||
| Non-smoker | (ref) | ||||
| Alcohol consumptiona | Alcohol consumer | 1.16 (0.61–2.21) | 0.65 | ||
| Non-consumer | (ref) | ||||
| Comorbidities | No comorbidities | (ref) | (ref) | ||
| Diabetes | 1.46 (1.03–2.08) | 0.034 | 1.72 (1.15–2.58) | 0.009 | |
| Hypertension | 1.35 (0.94–1.93) | 0.101 | 1.75 (1.16–2.64) | 0.008 | |
| Asthma/chronic obstructive pulmonary disease | 0.56 (0.28–1.13) | 0.104 | 0.49 (0.24–1.02) | 0.056 | |
| CAD/heart disease | 2.21 (0.52–9.33) | 0.281 | 2.46 (0.59–10.23) | 0.216 | |
| Any two or more comorbidities | 1.19 (0.79–1.76) | 0.395 | 1.46 (0.97–2.21) | 0.073 | |
| Presence of symptoms**,a | Yes | 1.09 (0.91–1.32) | 0.329 | ||
| No | (ref) | ||||
| Close contact with confirmed casesa | Yes | 1.00 (0.82–1.22) | 0.998 | ||
| No | (ref) | ||||
| Mask usage (public places) | Cloth | (ref) | (ref) | ||
| Surgical | 1.38 (1.13–1.28) | 0.001 | 1.15 (0.89–1.47) | 0.271 | |
| N95 | 0.97 (0.67–1.39) | 0.868 | 0.80 (0.52–1.23) | 0.316 |
*< 12 years of formal education
**Suggestive of recent respiratory infection in the last 6 months
a
This factor was not included in the multivariate analysis because it was not significant in the univariate analysis