Table 1. Sleep duration according to demographic and socioeconomic variables in the adult population (20 years old or more). Campinas, State of São Paulo, Brazil, 2014–2015.

Variable		Sleep Duration (%)			p*
		≤ 6 hours (n = 478)	7 to 8 hours (n = 1020)	≥ 9 hours (n = 501)
Sex					< 0.01
	Female	23.9	53.7	22.4
	Male	31.9	51.9	16.2
Age group (years)					< 0.01
	20 to 39	26.3	53.4	20.3
	40 to 59	33.6	53.5	13.0
	60 or more	20.1	50.3	29.7
Marital status					0.01
	Married/Living together	27.6	54.0	18.4
	Separated/Divorced	36.2	47.3	16.5
	Widower	20.5	44.7	34.8
	Never married	27.1	54.6	18.4
Race					0.40
	White	28.5	52.7	18.8
	Black and brown	25.5	53.1	21.4
Schooling (years)					< 0.01
	0 to 3	18.8	52.0	29.2
	4 to 8	23.8	51.9	24.3
	9 to 11	28.5	52.5	19.0
	12 or more	34.1	54.5	11.4
Per capita family income					< 0.01
	< 1 minimum wage	24.3	51.6	24.1
	1 to 2	31.6	50.3	18.2
	3 or more	23.2	63.6	13.2
Work status					< 0.01
	Not working	22.0	47.4	30.7
	Working	31.0	55.8	13.2
Number of inhabitants in the residence					0.02
	1	28.7	44.6	26.7
	2	23.1	51.3	25.6
	3 or more	28.7	54.0	17.3
Number of children					0.12
	0	25.3	55.7	19.0
	1	30.3	52.1	17.6
	2 or more	26.0	50.6	23.4
Health insurance					< 0.01
	No	24.1	52.2	23.7
	Yes	31.7	53.5	14.8

^*Rao-Scott chi-square test.