Table 2. Demographic Variables.

		Overall	Bus Drivers	Rickshaw Drivers	p-value**
		n = 505	n = 278	n = 227
Age	mean	36.9	40.4	32.3
	O-SD	12.1	12.1	11.1	<0.001
	BC-SD	6.2	5.9	5.2
	WC-SD	10.4	10.7	10.2
	p-value*	<0.001	<0.001	<0.001
Male Sex	Prevalence	96.3%	99.3%	92.7%
	O-SD	20.5%	8.5%	26.1%	<0.001
	BC-SD	6.5%	2.0%	7.2%
	WC-SD	19.9%	8.3%	25.7%
	p-value*	0.418	∼1.000	∼1.000
Number of children	mean	2.3	2.8	1.7
	O-SD	1.9	2.0	1.6	<0.001
	BC-SD	0.8	0.7	0.4
	WC-SD	1.7	1.9	1.6
	p-value*	<0.001	0.002	0.162
Married or Co-habitants	Prevalence	67.9%	71.7%	62.5%
	O-SD	47.3%	45.1%	48.5%	0.114
	BC-SD	15.0%	15.2%	17.6%
	WC-SD	45.2%	43.8%	45.4%
	p-value*	0.002	0.273	0.001
Divorced	Prevalence	6.9%	9.8%	3.1%
	O-SD	25.9%	29.8%	17.4%	0.003
	BC-SD	6.8%	9.9%	5.1%
	WC-SD	25.2%	28.9%	17.1%
	p-value*	0.127	0.470	∼1.00
Complete Secondary School	Prevalence	62.6%	64.4%	61.8%
	O-SD	48.0%	48.0%	48.7%	0.671
	BC-SD	15.8%	20.0%	14.0%
	WC-SD	46.2%	45.5%	47.9%
	p-value*	0.035	0.015	∼1.000
Complete Superior Education	Prevalence	20.2%	22.9%	15.9%
	O-SD	39.9%	42.1%	36.7%	0.186
	BC-SD	15.5%	17.3%	14.6%
	WC-SD	37.7%	39.3%	35.2%
	p-value*	<0.001	<0.001	0.184
Migrants	Prevalence	62.7%	63.8%	61.3%
	O-SD	48.6%	48.1%	48.8%	0.565
	BC-SD	18.2%	15.1%	22.1%
	WC-SD	47.1%	47.1%	46.9%
	p-value*	∼1.000	∼1.000	0.354
Time of residence in Lima	mean	25.5	28.4	21.6
	O-SD	14.0	15.5	11.6	0.001
	BC-SD	6.1	6.3	4.4
	WC-SD	12.9	14.3	11.2
	p-value*	<0.001	<0.001	0.205

O-SD: Overall Standard Deviation, BC-SD: Between cluster standard deviation, WC-SD: Within cluster standard deviation.

*p-value for the null hypotheses that between cluster is equal to zero.

**p-value for the null hypotheses that prevalence of measured variable does not vary according to job.