Received Aug 26; Accepted Nov 3. Friendship networks were derived using social network analysis in each grade. Adolescents and their friends also reported on their alcohol use, smoking, and sexual debut at each assessment. Thus, this is a key developmental period for the study of risk and protective factors related to the initiation and escalation of health risk behaviors. Specifically, friendships with other-sex peers are related to earlier sexual intercourse Billari and Mencarini and higher antisocial activity, especially among girls Arndorfer and Stormshak ; Haynie et al.
However, because boys exhibit higher levels of antisocial behavior and earlier initiation of sexual intercourse than girls Centers for Disease Control and Prevention , it is not clear whether other-sex friends exert negative influences on adolescent girls because of their gender or behavior. Other-Sex Friendships and Their Relationship to Problem Behavior Segregation by sex is a well-characterized feature of friendships that emerges in early childhood LaFreniere et al.
Although most preadolescent friendships are with same-sex peers, the number of other-sex friendships increases throughout adolescence Poulin and Pedersen However, the features of other-sex friendships vary by gender.
Adolescent girls report having more other-sex friends than boys, and their other-sex friendships are more likely to occur outside of school and with older peers.
These gender differences emerge early in adolescence and increase over time Poulin and Pedersen Although youth conceptualize other-sex friendships as clearly distinct from romantic relationships Connolly et al. In mixed-sex groups, adolescents learn how to relate to the other sex, leading to lower anxiety in social and dating heterosexual situations LaGreca and Mackey and greater subsequent engagement in romantic relationships Connolly et al. These positive functions of other-sex friendships notwithstanding, recent literature also links such friendships with negative behaviors, such as earlier sexual intercourse, higher alcohol use, and antisocial activity.
Specifically, college students who retrospectively reported having opposite-sex friends in adolescence also reported earlier engagement in sexual intercourse Billari and Mencarini The findings were significant for both sexes, but the effects were stronger for males than females.
Another study addressing substance use Dick et al. Similarly, Arndorfer and Stormshak found that nominating an opposite-sex peer as one of three best friends was associated with concurrent antisocial behavior for girls, but not boys, in 6th grade. Although these concurrent associations did not emerge in 7th or 8th grade, nominating an opposite-sex best friend in 6th and 8th grade predicted subsequent antisocial behavior.
Additional analyses revealed that, for girls, other-sex friendships were linked with higher violence only when the friends reported higher levels of violent behavior. These results indicated that, for girls, friendships with violent boys were associated with increased violence over time, but friendships with non-violent boys were not.
However, the girls in this study reported very low rates of violence overall, so the results may not generalize to problem behaviors that are more common among females. Altogether, this literature suggests that other-sex friendships are associated with problem behaviors in adolescence and that these relationships may vary by sex. Alternative Explanations of Other-Sex Friendship Effects However, it is not clear whether other-sex friendships actually contribute to problem behavior.
For instance, it is possible that adolescents who are more sexually experienced or who use substances are more likely to develop other-sex friendships, or that both problem behaviors and other-sex friendships result from other common causes.
In particular, we focus on substance use and sexual debut, which are the outcome behaviors examined in this study. Given the consensus in the literature that the primary functions of mixed-sex friendship groups are to provide access to potential romantic partners and to develop interpersonal skills that would facilitate heterosexual romantic relationships Connolly et al.
Indeed, mixed-sex friendships increase the likelihood of heterosexual dating Connolly et al. Although the association may be more tenuous, other-sex friendships could also lead directly to increased substance use among adolescents.
If adolescents viewed the use of alcohol and tobacco as common, desirable and appealing to the other-sex, they may initiate or escalate substance use to impress and be liked by other-sex friends. It is notable that adolescents typically overestimate the prevalence of substance use among their peers Page et al.
Although little research has addressed substance use norms and expectations for the other sex, a recent study with college students showed that females overestimate the amount of alcohol males want their female friends and partners to drink; importantly, this overestimation contributed to higher levels of drinking among these young women LaBrie et al. Another potential pathway explaining increased substance use among those with opposite-sex friends could be the use of tobacco and alcohol to reduce anxiety associated with heterosexual interactions, such as at mixed-sex parties and gatherings.
Thus, other-sex friendships may facilitate sexual debut through increased opportunities for dating, and they may contribute to substance use through biased perceptions of other-sex norms and expectations regarding substance use, as well as through anxiety reduction motives.
A large literature demonstrates peer influences on both substance use and sexual behavior e. One Gender May be More Susceptible to Peer Influence Another possibility is that girls may be more susceptible to peer influence in general i. However, it should be noted that existing findings on sex differences in susceptibility to peer influence are mixed, with some studies not finding sex differences Fuemmeler et al. Behavior of other-sex friends might be more influential if these friendships are valued more than same-sex relationships e.
However, given recent evidence suggesting greater propensity of girls to alter their behavior in cross-sex friendships compared with boys McDougall and Hymel , it may extend to other domains as well. Peer Influences May Vary with Development The influence of other-sex friendships may be further modified by developmental factors.
Perhaps due to greater maturity and more strongly established self-identity, self-reported resistance to peer influence increases from middle to late adolescence Steinberg and Monahan Likewise, self-reported susceptibility to peer influence generally increases in early to middle adolescence and then decreases in late adolescence Berndt However, studies that examined developmental differences in the actual effects of peer behavior have not always confirmed these self-report trends.
For instance, one study found no differences in peer influences on adolescent smoking between 6th and 11th grade Chassin et al. Thus, although some literature suggests that same-sex and other-sex friends and friendships may become more influential as adolescents progress through the high school years, other developmental trends may also occur.
Given the scarcity of controlled longitudinal studies, the directionality of the associations is also unclear. Consistent with existing literature on adolescent peer relationships, we conceptualize friendship influence as present within friendship groups or cliques, defined as cohesive groups of youth who regularly interact with each other Urberg et al.
Methods Participants and Procedures Participants were adolescents enrolled in a larger study of social and academic development of youth. The study was conducted in a public school district in a mid-sized town in the Northeast of the U.
The present report includes data collected in three successive years — from a cohort of adolescents attending the same grade in one high school as they progressed from 10th to 12th grade approximate ages 16— The numbers of participating students were , , and out of , , and students officially listed in grades 10, 11, and 12, respectively. However, because the analyses used listwise deletion of cases with missing data, participants who did not have complete data for all variables used in a given analysis were excluded from that analysis.
The number of cases used in individual analyses thus ranged from to A total of adolescents were used in one or more analyses. Main reasons for attrition were not being officially listed on the class roster in two consecutive years e. Each data collection was conducted in the spring to ensure sufficient familiarity of students with one another in order to yield valid and reliable sociometric data. Adolescents completed group-administered peer nomination and self-report forms in their classrooms.
Identical measures were used at each data collection wave. The two items were averaged within each grade. Combining the frequency of use with the frequency of binge drinking is a commonly used measure of adolescent substance use e. Sexual Debut One dichotomous item assessed adolescent self-report of ever having sexual intercourse.
Proportion of Other-Sex Friends As a part of the sociometric nominations, adolescents were asked to nominate their best friends within the entire grade. Students could nominate as many best friends as they liked; both same-sex and other-sex nominations were allowed.
Dyads are groups in which both students nominated each other as friends. Groups of three include a dyad in which at least one person is reciprocally connected to another person.
Groups of four are dyads where both people are reciprocally connected to other students, who may or may not be connected to others in the group. So, each friendship group has at least one dyad and all other connections must adhere to the principle of transitivity. Thus, no student is more than one reciprocal tie from any other student in the friendship group. This method has been used successfully in previous peer relations studies e. Friendship groups ranged in size from 2 to 9—11 peers across the three grades.
For each adolescent, we then computed the proportion of his or her friends who were of opposite-sex.