Risk factors for chronic periodontitis in Sri Lankan adults: a population based case–control study

BMC Research Notes

Table 1 Comparison socio-demographic exposure variables between cases and controls

Variable	Cases (694)		Controls (706)		p value
Variable	n	%	n	%	p value
Sex
Female	261	37.6	419	59.3	<0.001
Male	433	62.4	287	40.7
Age group (years)
30–44	298	42.9	374	53.0	<0.001
45–60	396	57.1	332	47.0
Ethnicity
Sinhala	545	82.4	581	79.2	0.033
Tamil	75	11.5	81	10.9
Muslim	68	6.1	43	9.9
Level of education (years)
0–5	86	12.4	50	7.1	<0.001
6–10	277	39.9	197	27.9
11–12	299	43.1	401	56.8
>12	32	4.6	58	8.2
Monthly household income (Rupees)
≤20,000	494	71.2	512	72.5	0.57
>20,000	200	28.8	194	27.5
Current occupation^a
Low category	568	81.8	526	74.5	0.001
High category	126	18.2	180	25.5

For all variables but ethnicity, the total number of cases and controls were 694 and 706 respectively. With regards to ethnicity, seven participants who belonged to minor races were excluded in the analysis; cases = 688 and control = 705)
^aLow = unskilled/skilled larbourer, unemployed for males, housewife, lower business; high = professional, managerial, clerical, technical, upper business

ISSN: 1756-0500