Table 2.

Measures

Covariates	No. of items	Response options	Exact/sample item	Scoring	Reliability (Cronbach’s alpha)a
Biological sex	1	Male; female	“What is your sex?”	Dichotomized to 1 = male and 0 = female	—
Grade level	1	Sixth; seventh; eighth	“What is your current grade?”	Categorized as 0 = sixth grade, 1 = seventh grade, and 2 = eighth grade	—
Site	1	A; B; C; D	Determined on survey form	Dummy variables for each site (e.g., Site A = 1 and not Site A = 0)	—
Race/ethnicityb	2	Yes; no	“Are you Hispanic or Latino?”	Students were classified as “Hispanic/Latino” if they answered “yes” to the first question, regardless of how they answered the second question.
		American-Indian or Alaska Native; Asian; black or African-American; Native Hawaiian or other Pacific Islander; white; and other	“What is your race? Mark one or more.”	Students who answered “no” to the first question and selected only one additional race category, for example black or African-American, were classified as “non-Hispanic black”. When a student answered “no” to the first question and selected multiple racial groups in the second question, they were classified as “mixed.” Due to small cell sizes for some categories, the mixed group was combined with American-Indian or Alaska Native, Asian, Native Hawaiian or other Pacific Islander, and other to create the race/ethnicity category of “other.”	—
Exposure to family violence	1	Yes; no	“At any time in your life, did you see a parent get pushed, slapped, hit, punched, or beat up by another parent, or their boyfriend or girlfriend?”	Dichotomized to 1 = yes and 0 = no	—
Exposure to community violence	1	Yes; no	“At any time in your life, in real life, did you see anyone get attached on purpose with a stick, rock, gun, knife, or other thing that would hurt? Somewhere like at home, at school, at a store, in a car, on the street, or anywhere else?”	Dichotomized to 1 = yes and 0 = no	—
Predictor variables
Alcohol usec	2	Never; one or two times; three to five times; six to nine times; 10 or more times	“In the last year, how many times have you been drunk?”	Items summed to create a total score and dichotomized to 1 = one or more times and 0 = never for analyses	.687
Illicit drug usec	4	Never; one or two times; three to five times; six to nine times; 10 or more times	“In the last year, how many times have you used marijuana or weed (pot, hash, reefer)?”	Items summed to create a total score and dichotomized to 1 = one or more times and 0 = never for analyses	.357
Bullyingd		Never; one or two times; three or four times; five or more times	“In the last 30 days at school, how often did this happen? … I spread rumors about other students.”	All bullying variables were binary and categorized such that perpetration only = endorsement of perpetration, but no victimization; victimization only = endorsement of victimization but no perpetration; perpetration and victimization = endorsement of both perpetration and victimization. For all variables, referent = no experience with either bullying perpetration or victimization.	Perpetration = .828
Perpetration	8				Victimization = .885
Victimization	2
Emotional symptomse	5	Not true; somewhat true; certainly true	“Please give your answers based on how things have been for you in the last 6 months … I worry a lot.”	Items summed to create a total score and kept continuous	.680
Attitudes toward female violencef	5	Strongly agree; somewhat agree; somewhat disagree; strongly disagree	“These statements are about hitting in situations in which boys and girls are dating. How strongly do you agree or disagree with each statement? …It is OK for a girl to hit her boyfriend if he did something to make her mad.”	Items summed to create a total score and kept continuous	.865
Attitudes toward male violencef	5	Strongly agree; somewhat agree; somewhat disagree; strongly disagree	“These statements are about hitting in situations in which boys and girls are dating. How strongly do you agree or disagree with each statement? …It is OK for a boy to hit his girlfriend if she insulted him in front of friends.”	Items summed to create a total score and kept continuous	.920
Delinquency and peer violencef	7	Never; one or two times; three or four times; five or more times	“In the past 4 months, how often did you deliberately damage property that did not belong to you (including painting graffiti or signs)?”	Items summed to create a total score and kept continuous	.742
Initiation of sexual intercourseg	1	Yes; no	“Have you ever had sexual intercourse?”	Dichotomized 1 = yes and 0 = no for analysis	—
Weapon carryingh	1	0 days; 1 day; 2 or 3 days; 4 or 5 days; 6 or more days	“During the past 30 days, on how many days did you carry a weapon such as a gun, knife, or club?”	Dichotomized to 1 = at least 1 day and 0 = 0 days for analysis	—
Outcome variables:			The following questions ask you about things that may have happened with a boyfriend/girlfriend. How often have these things ever happened with someone you were dating …
CADRI Scalesi
Sexual abuse	4	Never; seldom; sometimes; often	“I forced him/her to have sex when he/she did not want to.”	Items summed to create a total score for the subscale and dichotomized to 1 = seldom, sometimes, or often and 0 = never for analysis	.527
Threatening behavior	4	Never; seldom; sometimes; often	“I destroyed or threatened to destroy something he/she valued.”	Items summed to create a total score for the subscale and dichotomized to 1 = seldom, sometimes, or often and 0 = never for analysis	.687
Verbal or emotional abuse	10	Never; seldom; sometimes; often	“I insulted her with put downs.”	Items summed to create a total score for the subscale and dichotomized to 1 = seldom, sometimes, or often and 0 = never for analysis	.837
Relational abuse	3	Never; seldom; sometimes; often	“I tried to turn his/her friends against him/her.”	Items summed to create a total score for the subscale and dichotomized to 1 = seldom, sometimes, or often and 0 = never for analysis	.478
Physical abuse	4	Never; seldom; sometimes; often	“I kicked, hit, or punched him/her.”	Items summed to create a total score for the subscale and dichotomized to 1 = seldom, sometimes, or often and 0 = never for analysis	.801
Outcome variables:			Have you ever done the following to someone you were dating or used to date …
Stalkingi	2	Yes; no	“Repeatedly followed, harassed, and contacted them when they didn’t want to be (and in a way that felt uncomfortable, scary, or threatening to them)?”	Items summed to create a total score and dichotomized to 1 = yes and 0 = no for analysis	.506

CADRI = Conflict in Adolescent Dating Relationships Inventory.

^aWe calculated alpha values for all our scale measures, which is appropriate as scale measures have items that reflect the “effects” of the latent construct and therefore must be correlated as well as the index measures such as the CADRI. However, items that constitute indexes are usually items that are combined to form the index without consideration of their correlations. Index items are considered as causal indicators that “cause” the concept and may not be correlated; thus, they would or may have a low coefficient alpha, which does not reflect low reliability for the population in which the index was administered [40].

^bCenter for Disease Control and Prevention’s Youth Behavioral Risk Survey methodology for handling race/ethnicity was used as a guide [41].

^cAdapted from the LINKAGE items used in University of Illinois Bully Scale (UIBS), Espelage and Holt, 2001 [42].

^dUIBS, Espelage and Holt, 2001 [42].

^eStrengths and Difficulties Questionnaire, Goodman, 1997 [43].

^fFoshee et al., 1998 [9].

^gAdapted from Add Health; Udry, 2003 [44].

^hYouth Risk Behavior Survey, CDC, 2011 [41].

ⁱWolfe et al., 2001 [25].

^jTwo items were adapted from the seven-item National Intimate Partner and Sexual Violence Survey [26] to assess stalking through physical presence behaviors and communications behaviors. Full references for measures from which questions were adapted are available upon request.