Table 3. Prevalence rate ratio (PR) of geohelminths before and after the city-wide sanitation intervention, adjusted for confounding and intervention variables.
| Prevalence Ratio (PR) | Any Geohelminth (95% CI) | AF*% | Ascaris lumbricoides (95% CI) | AF*% | Trichuris trichiura (95% CI) | AF* % | Hookworms (95% CI) | AF*% |
| PR (crude) | 0.74 (0.57–0.89) | — | 0.77 (0.64–0.92) | — | 0.67 (0.56–0.79) | — | 0.17 (0.09–0.29) | — |
| PR adjustedA | 0.73 (0.66–0.81) | — | 0.75 (0.63–0.87) | — | 0.67 (0.58–0.79) | — | 0.18 (0.09–0.33) | — |
| PR adjustedB | 0.74 (0.66–0.83) | 3.7 | 0.76 (0.63–0.91) | 4.0 | 0.68 (0.58–0.75) | 3.0 | 0.17 (0.09–0.29) | −1.2 |
| PR adjustedC | 0.72 (0.65–0.80) | −3.7 | 0.74 (0.62–0.87) | −4.0 | 0.66 (0.58–0.75) | −3.0 | 0.17 (0.09–0.31) | −1.2 |
| PR adjustedD | 0.77 (0.68–0.88) | 14.8 | 0.81 (0.66–0.98) | 24.0 | 0.71 (0.59–0.86) | 12.1 | 0.20 (0.11–0.37) | 2.4 |
| PR adjustedE | 0.96 (0.89–1.04) | 85.2 | 1.14 (0.97–1.36) | 100 | 0.83 (0.74–0.91) | 48.5 | 0.23 (0.09–0.56) | 6.1 |
| PR adjustedF | 1.24 (0.98–1.58) | 100 | 1.72 (1.26–2.34) | 100 | 1.06 (0.72–1.58) | 100 | 0.37 (0.12–1.09) | 23.2 |
*: AF = Proportion of reduction attributable fraction of intervention variable.
 |
Ratio adjusted for confounding: age and sex of child, paving of street, number of children <5 years in household, mother's education and presence of sewage in 1997.
Ratio adjusted for variable of intervention = presence of drainage system of rainwater and for confounding A.
Ratio adjusted for variable of intervention = absence of open refuse collection points and for confounding A.
Ratio adjusted for variable of intervention = frequency of water supply and for confounding A.
Ratio adjusted for variable of intervention = proportion of households connected to the Bahia Azul sewage system and confounding A.
Ratio adjusted for all variables of intervention B+C+D+E and for confounding A.