Table 3. Sexual initiation: Associations with substance use, school attachment and positive parent communication, controlling for demographics.

	DEPENDENT VARIABLE: SEXUAL INITIATION
	Model 1: Substance Use		Model 2: School Attachment		Model 3: Positive Parent Communication
	Boys (n=2,722) AORa	Girls (n=2,902) AORa	Boys (n=2,722) AORa	Girls (n=2,902) AORa	Boys (n=2,722) AORa	Girls (n=2,902) AORa
Family composition
Two biologic parents	Ref.	Ref.	Ref.	Ref.	Ref.	Ref.
Stepfamily	2.08***	1.73***	2.11***	2.25***	2.16***	2.15***
Single parent	1.63***	1.61***	1.52***	1.60***	1.56***	1.67***
Other	2.28*	3.97***	2.14*	3.43**	2.41**	3.37**
Family SES
Low	1.30*	1.56**	1.18	1.32*	1.23†	1.38**
Medium	1.04	1.41*	1.03	1.19	1.03	1.20§
High	Ref.	Ref.	Ref.	Ref.	Ref.	Ref.
Nation
United States	Ref.	Ref.	Ref.	Ref.	Ref.	Ref.
Scotland	0.64**	0.44***	1.15	1.25†	1.10	1.07
Finland	0.25***	0.39***	0.35***	0.66*	0.45*	0.53*
Franceb	0.69*	0.39***	0.85	0.51***	1.23	0.48**
Poland	0.60**	0.21***	1.01	0.30***	1.09	0.23***
Substance use	1.56***	2.02***	--	--	--	--
School attachment	--	--	0.81**	0.69***	--	--
Positive parent communication	--	--	--	--	0.84	0.50**
Interactions
IVc × Scotland	1.47**	1.81***	0.99	1.08	1.24	1.48§
IVc × Finland	2.40***	1.57**	0.78†	1.12	1.36	2.05*
IVc × France	1.61**	1.17	0.81†	1.01	0.88	1.54
IVc × Poland	1.85***	1.30§	1.04	1.36†	0.96	1.63

^aAOR = Adjusted odds ratio from multivariable logistic models; p-values reflect robust standard errors

^bFrance was represented by two regions only in the 1998 HBSC.

^cIV = independent variable

^§p<0.20

^†p<0.10

^*p<0.05

^**p<0.01

^***p<0.001