Table 3.

Job characteristics of interviewees.

Statistical Items	Values	Percentage
Daily working hours	$\le$8 h	6.4%
	8–10 h	44.5%
	10–12 h	27.3%
	>12 h	21.8%
Working day of each week	<5	7.7%
	5–6	28.2%
	7	64.1%
Daily delivery order quantity	<30	12.3%
	30–40	27.7%
	40–60	41.8%
	>60	18.2%
Monthly income	<5000	20.9%
	5000–7000	34.6%
	7000–10,000	30.9%
	>10,000	13.6%
Average sleep time	<6 h	46.4%
	6–8 h	40.5%
	>8 h	13.1%