Table 1.

Characteristics of Participants in the Study Stratified for Internet and Written Mode of Questionnaire Administration (n = 933)

	Internet mode of administration (n = 458)		Written mode of administration (n = 475)		P-value
	n	% of participants	n	% of participants	Internet versus written mode
Age
13–14 years	189	41.3%	210	44.2%	0.361
15–17 years	269	58.7%	265	55.8%
Gender
Female	257	56.1%	244	51.4%	0.171
Born in the Netherlands
Yes	425	92.8%	441	92.8%	0.901
Educational level of the school
Lower secondary	271	59.1%	274	57.7%	0.882
Intermediate secondary	85	18.6%	94	19.8%
Higher secondary	102	22.3%	107	22.55

¹Chi squared test df = 1.

²Chi squared test df = 2.