Table 2. Mediation analysis results of HPV-16 infection for current and former smokers compared to never smokers.
| Current Smokera | Former Smokera | |||
|---|---|---|---|---|
| OR | 95% CI | OR | 95% CI | |
| Overall associationb | 1.08 | (0.71, 1.62) | 1.02 | (0.54, 1.91) |
| Mediator adjusted associationb,c | 1.03 | (0.68, 1.55) | 1.01 | (0.54, 1.89) |
| Causal mediation analysis | ||||
| Total natural indirect effect | 1.29 | (1.11, 1.73) | 1.10 | (0.98, 1.53) |
| Pure natural direct effect | 0.57 | (0.26, 1.13) | 0.61 | (0.20, 1.30) |
| Causal mediation analysis without smoking-antibody interaction term | ||||
| Total natural indirect effect | 1.08 | (1.01, 1.18) | 1.03 | (1.00, 1.13) |
| Pure natural direct effect | 1.03 | (0.67, 1.47) | 1.00 | (0.48, 1.66) |
all models adjusted for model covariates: age, age at sexual debut, and lifetime number of sexual partners
a
never smokers are the referent category
b
the traditional method assesses the degree of attenuation between the overall association and the mediator adjusted association; higher attenuation suggests more of an indirect effect, less attenuation suggests more of a direct effect
c
additionally adjusted for the mediator, HPV-16 antibody status