Table 5.
Poisson regression model (with interaction term between initial number of nodules and treatment arms)
| Variable | Saturated model | Stepwise model | ||
|---|---|---|---|---|
| b (95% CI) | P-value | b (95% CI) | P-value | |
| Increase in no. of new nodules for each additional initial nodulea | ||||
| 150 µg/kg annually | 0.043 (0.014–0.071) | 0.004 | 0.046 (0.019–0.073) | 0.001 |
| 800 µg/kg annually | 0.067 (0.039–0.095) | < 0.001 | 0.070 (0.043–0.096) | < 0.001 |
| 150 µg/kg 3-monthly | 0.021 (− 0.004–0.047) | 0.106 | 0.024 (− 0.000–0.048) | 0.052 |
| 800 µg/kg 3-monthly | 0.026 (− 0.001–0.053) | 0.063 | 0.029 (0.004–0.056) | 0.026 |
| Age | 0.005 (− 0.00001–0.010) | 0.051 | 0.006 (0.002–0.009) | 0.003 |
| Weight | − 0.001 (− 0.005–0.003) | 0.659 | ||
| CMFL in the village of residence | ||||
| Low | Ref. | |||
| Middle | 0.090 (− 0.154–0.333) | 0.470 | ||
| High | 0.151 (− 0.072–0.375) | 0.185 | ||
| MFD | ||||
| 0–30 mf/mg | Ref. | Ref. | ||
| 31–80 mf/mg | 0.089 (− 0.103–0.281) | 0.364 | 0.105 (− 0.079–0.288) | 0.263 |
| 81–170 mf/mg | 0.278 (0.095–0.461) | 0.003 | 0.301 (0.128–0.474) | 0.001 |
| > 171 mf/mg | 0.371 (0.194–0.549) | < 0.001 | 0.394 (0.227–0.561) | < 0.001 |
| P of the likelihood-ratio test for the interaction term: 0.035 | ||||
| P of the model | < 0.001 | < 0.001 | ||
| AIC | 1649 | 1645 | ||
| BIC | 1695 | 1678 | ||
| Log likelihood | − 813.5 | − 814.6 | ||
aThe reference is defined as 150 µg/kg annually and 2 initial nodules
Abbreviations: b, regression coefficient; 95% CI, 95% confidence interval; Ref., reference; CMFL, community microfilarial load; MFD, microfilarial density; AIC, Akaike’s information criterion; BIC, Bayesian information criterion