Table 2.

Reasons for changing one’s response according to demographic and drug use characteristics

	Did Not Read Question Carefully	Do Not Really Care About Survey	Other Reason
	Weighted %	Weighted %	Weighted %
Age (Trichotomy)
18–24 years	60.2	13.5	26.3
25–29 years	49.2	42.6	8.2
≥30 years	75.4	9.4	15.2
Sex
Male	74.3	10.5	15.3
Female	42.7	37.9	19.4
Race/Ethnicity
White	51.2	36.6	12.2
Non-White	75.2*	5.2	19.6
Education
Less Than College Degree	75.7	12.5	11.8
College Degree	59.4	21.7	19.0
Sexual Orientation
Heterosexual	67.0	20.8	12.1
Non-Heterosexual	57.3	9.3	33.4
Where Surveyed
Nightclub	70.8**	19.3	9.9
Festival	20.0	12.0	68.0
Lifetime Drug Use
Ecstasy
No	64.0	21.0	15.0
Yes	70.9	3.9	25.2
Powder Cocaine
No	65.2	21.0	13.8
Yes	64.0	4.9	31.1
LSD
No	66.8*	19.1	14.1
Yes	32.5	8.0	59.5
Ketamine
No	67.1***	18.9	14.0
Yes	15.9	8.9	75.2
Methamphetamine
No	66.0	19.1	15.0
Yes	50.7	9.3	40.0
Honesty to Responses
All	81.9*	5.8	12.3
Most	49.9	39.6	10.5
Less Than Most	25.0	33.0	42.0

Note. Some categories were collapsed in order to ensure enough participants per cell. 65.0% reported underreporting because they did not read the question carefully, 18.5% reported not really caring about the survey, and 16.5% reported underreporting for another reason.

^*p < .05,

^**p<.01,

^***p<.001