Table 7.

The mediation effect of NBSP for commuting times longer than 50 min increasing WB

	Dependent variable: WB		Mediating factor: NBSP
Independent variable	c	c’	a	sa	b	sb	Z
Commuting time > 50 vs. others	1.39	0.07	0.21**	0.081	6.32***	0.413	2.56
Private vehicle or Motorcycle	1.03*	1.67**	−0.10**	0.030	6.43***	0.412	−3.26

^*, P < 0.05; ^**, P < 0.001; ^***, P <.0001; c, the linear regression coefficient of independent variable against dependent variable in absence of mediating factor; c,’ the linear regression coefficient of independent variable against dependent variable in presence of mediating factor; a, the linear regression coefficient of independent variable against mediating factor; b, the linear regression coefficient of mediating factor against dependent variable; s_a; the standard errors of a; s_a; the standard errors of b