Swahn et al. Reciprocal Dating Violence and Injury Occurrence Table 2. Severity of nonreciprocal and reciprocal dating violence in the past year among adolescents who reported any dating violence (n=1,158). p-value2 <.00001 <.001 Violence frequency Low Medium/High n (%) n (%) Injury occurrence Yes No n (%) n (%) p-value1 <.0001 .2396 <.0001 7 (1.2) 48 (10.1) 36 (7.4) 18 (3.2) 6 (2.0) 30 (16.0) *3 17 (6.0) 571 (98.8) 428 (89.9) 447 (92.6) 549 (96.8) 290 (98.0) 157 (84.0) 281 (99.6) 268 (94.0) Reciprocity Nonreciprocal Reciprocal Participant’s sex Boy (against partner) Girl (against partner) Participant’s sex by reciprocity Boy against partner: nonreciprocal Boy against partner: reciprocal Girl against partner: nonreciprocal Girl against partner: reciprocal 1 Pearson’s Chi-Square test of association. 2 Fisher’s Exact test of association. 3 Cell size smaller than 5 and not reported. 403 (64.0) 72 (15.1) 227 (47.3) 248 (43.7) 194 (66.0) 33 (17.7) 209 (74.1) 39 (13.6) 173 (30.0) 404 (84.9) 253 (52.7) 320 (56.3) 100 (34.0) 153 (82.3) 73 (25.9) 247 (86.4) Measures The dating-violence measures used in the current study were adapted from previous research14,15 and the modifications are described elsewhere.2,3,12 Briefly, dating violence perpetration and victimization were assessed through two identical 10-item scales to determine if participants had experiences with certain forms of violence (e.g., scratched, hit or slapped, threw something that could hurt, slammed or held against wall, kicked, pushed, grabbed or shoved, punched or hit with something that could hurt, threatened with a weapon, forced to have sex, and hurt badly enough to need bandages or care from a doctor or nurse) in the past 12 months. Response options for each scale were as follows never, 1-3 times, 4-9 times, and 10 or more times. Analyses The current analyses were restricted to those who reported dating in the past year and who also reported any dating violence (n=1,158). The data were grouped into four categories of dating violence: 1) No dating violence; 2) Dating violence victimization only; 3) Dating violence perpetration only; and 4) Dating violence reciprocity (both victimization and perpetration). Because responses to the dating violence frequency measure were not normally distributed (negatively skewed), and there were small cell sizes within levels of some of the independent measures, the median was used to group the violence data into two ordinal categories to indicate low or medium-high violence frequency. We conducted Chi Square and Fisher’s exact tests to determine if there were statistically significant associations with reciprocity (nonreciprocal vs. reciprocal) and differences in categorical demographic variables (by gender, race/ethnicity and grade level), as well as violence frequency and injury occurrence. RESULTS There was a statistical difference between boys and girls in terms of reporting reciprocal dating violence (p<.0001) (Table 1). Among those who reported any dating violence, 38.9% of boys and 50.4% of girls reported reciprocal violence. There were no statistical significant differences in terms of reciprocity and participants’ race/ethnicity or grade level. Reciprocity was associated with the frequency of violence (p<.0001) and of injury occurrence (P<.00001), with reciprocal violence associated with more frequent violence and greater injury occurrence (Table 2). However, participant’s sex was not associated with violence frequency but was associated with injury occurrence (p<.001). Boys were more likely to report injuries than were girls. DISCUSSION Our study of urban youth in a high-risk community shows that reciprocal dating violence is relatively common among those engaging in dating violence; 38.9% of boys and 50.4% of girls reported reciprocal dating violence. Moreover, the study found that when violence is reciprocal, violence is more frequent, and there are also more reports of injuries. These findings corroborate research on adults5 and highlight that prevention efforts that seek to reduce injuries from dating violence may need to target reciprocity specifically. More importantly, since reciprocal dating violence is common among high school students in this study, prevention strategies that seek to reduce dating violence and related injuries among Volume XI, no. 3 : August 2010 266 Western Journal of Emergency Medicine