Water pipe smoking among public versus private university students in Ankara, Turkey: an online survey

BMC Public Health

Table 4 Ever smoked WP: Logistic regression estimates (aORs [95% CI]), SES index used as an associated factor

	Private University Students	Public University Students	All Students
Private university			1.54***
			[1.35,1.75]
Gender
Female	1	1	1
Male	2.31***	2.77***	2.53***
Male	[1.91,2.80]	[2.31,3.32]	[2.22,2.88]
Age group
Ages 18-19	1	1	1
Ages 20-21	1.40***	1.78***	1.58***
Ages 20-21	[1.10,1.79]	[1.37,2.30]	[1.32,1.88]
Ages 22-23	2.45***	2.13***	2.24***
Ages 22-23	[1.87,3.22]	[1.62,2.79]	[1.85,2.70]
Ages 24 or older	2.81***	3.29***	3.07***
Ages 24 or older	[1.88,4.22]	[2.34,4.62]	[2.37,3.97]
SES index	1.13***	1.12***	1.13***
SES index	[1.06,1.20]	[1.06,1.19]	[1.08,1.18]
Observations	2184	2352	4536

Notes: The SES index was calculated using the first principal component of eight binary variables (taking values of zero or one): Has a car, Lives with family, Lives in dormitory, Lives alone, Has roommate(s), Income source: Family support, Income source: Scholarship, Income source: Work. The first principal component had positive loadings on four variables (has a car, lives with family, lives alone, and receives family support). These four variables can be thought to be associated with higher socioeconomic status. The other four variables had negative factor loadings. The mean (and standard error) values of the index for private and public university students were 0.0966 (0.0302) and -0.0893 (0.0265), respectively. A two-sample t-test for difference in means yielded a t-statistic of -4.62; therefore, the null hypothesis of equality of means was rejected
The first two columns in the table show estimates of adjusted odds ratios (adjusted for all associated factors variables listed in the table) from binary logistic regressions, separately for private and public university students. The last column shows the estimates for the entire sample, adding the “Private university” dummy (binary) variable to the regression. 95% CI are shown in square brackets. ***p<0.01

ISSN: 1471-2458