Resubmission: Social network analysis of the dynamic relationship between adolescent smoking behaviour & peer influence

人们越来越关注青少年的健康行为。同辈压力通常被认为是解释青少年焦虑的一个关键因素。风险行为的吸收，但令人惊讶的是，很少有人对其发生的过程进行审查。最明显的是通过公开施加压力来尝试烟草、酒精或非法药物，干预措施旨在发展青少年？抵抗同伴压力的能力。同伴影响还通过形成规范性信念而更加微妙地发挥作用，例如，青少年认为大多数人吸烟，吸烟是青少年生活的正常组成部分。青少年热衷于融入他们的同龄人群体，并以他们周围的人为榜样。然而，还有其他机制在起作用，包括同伴选择，在同伴选择中，行为相似的人会发展友谊。希望与其他吸烟者成为朋友的青少年可能会把吸烟作为加入朋友团体的途径。同伴影响和同伴选择的结合导致了朋友群体的发展，其中吸烟和其他危险行为的流行率很高。这些过程造成了学校之间吸烟率的显著差异。该项目将使用现有的数据集，这些数据集来自MRC最近资助的一项研究，研究对象是南威尔士和布里斯托尔地区59所学校的10,000名学生。学生们被分三次要求说出他们最好的六个朋友，以及他们的友谊。使用新的统计方法，这些数据将使研究团队能够理清同伴影响和同伴选择的相对重要性。根据他们自身的特点、父母的影响和他们目前的朋友群体，将确定那些最容易吸烟的非吸烟者。这些模式在各个学校的稳定性将得到确认。在这项研究中，报告吸烟是通过收集唾液样本来验证的，并结合友谊数据，这将允许学生的准确性？关于他们朋友的报告？吸烟情况有待评估。这项工作的结果将对未来努力减少青少年吸烟和其他危险行为的设计具有重要意义。公众和媒体对这个问题非常关注，研究团队一定会发布这项工作的新闻稿，并在卡迪夫大学的网站上发布这项研究及其结果。

There is increasing concern regarding the health behaviours of adolescents. Peer pressure is often cited as a key factor explaining adolescents? uptake of risk behaviours, yet there has been surprisingly little scrutiny of the process by which this occurs. It is most obviously exerted through overt pressure to experiment with tobacco, alcohol or illicit drugs, and interventions aim to develop adolescents? skills to resist peer pressure. Peer influence also operates more subtly, through the development of normative beliefs, in which, for example, adolescents believe that the majority of the population smoke, and that it is a normal part of teenage life to take up smoking. Adolescents are keen to fit in with their peer group, and model their own behaviour on those around them. However, there are other mechanisms at play, including peer selection, in which those with similar behaviours develop friendships. Adolescents wishing to become friends with other smokers, may take up smoking as a gateway to joining that friendship group. The combination of peer influence and peer selection leads to the development of friendship groups in which the prevalence of smoking and other risk behaviours is high. These processes contribute to marked differences between schools in smoking prevalence.This project will use an existing dataset, collected from a recent MRC funded study of 10,000 students in 59 schools in South Wales and the Bristol area. Students were asked on three occasions to name their six best friends, and about their friendship. Using new statistical methods, these data will allow the research team to disentangle the relative importance of peer influence and peer selection. Those non-smokers most at risk of smoking uptake will be identified, in terms of their own characteristics, parental influence, and their current friendship groups. The stability of these patterns across schools will be identified. In the study, reported smoking was validated through the collection of saliva samples, and combined with the friendship data, this will allow the accuracy of students? reports of their friends? smoking to be assessed. The results of this work will have important implications for the design of future efforts to reduce adolescent uptake of smoking and other risk behaviours. There is immense public and media concern on this issue, and the study team will be sure to produce press releases of the work, as well as featuring the study and its results on the Cardiff University website.