Alcohol drinking as a mediator of the influence of smoking prevalence on second-hand smoke exposure in workplaces: a mediation analysis

Table 2 Sobel test of mediation for Alcohol drinking from smoking to SHS exposure

Sobel test of mediation for drinking	Total effect	Direct effect	Indirect effect	Proportion of total effect that is mediated
Model 1
Male: Smoking→SHS exposure	0.408**	0.382**	0.026**	6.4%
Female: Smoking→SHS exposure	0.359**	0.310**	0.049**	13.6%
Overall: Smoking→SHS exposure	0.405**	0.360**	0.045**	11.1%
Model 2
Male: Smoking →SHS exposure	0.386**	0.362**	0.024**	6.3%
Female: Smoking→SHS exposure	0.340**	0.293**	0.048**	14.1%
Overall: Smoking→SHS exposure	0.376**	0.334**	0.04**	10.6%

Note: **p < 0.01
Model 1-we only included independent variable (Smoking), dependent variable (SHS exposure) and mediate variable (Alcohol drinking) in the model
Model 2-Except independent, dependent and mediate variables, we also included control variable (age, ethnic, BMI, marriage, education attainment, yearly income, chronic disease, sleep duration, position and night-shift duty) in the model

ISSN: 1747-597X