Table 3 Path coefficients and indirect effects for mediation models.

Gender

− 0.071*

–0.078*

− 0.07

Age

− 0.039

0.087

0.011

Station segment

0.084*

− 0.033

0.024

Education level

0.015

0.029

0.052

Workplace learning examination stress

− 0.36***

0.347***

− 0.001

Sleep quality

0.091***

Shortcut motivation

− 0.271***

Workplace learning examination stress→safety performance(total effect)

− 0.127

− 0.201

− 0.054

Workplace learning examination stress→sleep quality→safety performance(indirect effect)

− 0.032

− 0.067

− 0.003

Workplace learning examination stress→shortcut motivation→safety performance(indirect effect)

− 0.094

− 0.130

− 0.062

Workplace learning examination stress→safety performance(direct effect)

− 0.001

− 0.081

0.078