Malagón Talía, Burchell Ann, El-Zein Mariam, Tellier Pierre-Paul, Coutlée François, Franco Eduardo L
From the *Division of Cancer Epidemiology, Department of Oncology, McGill University, Montréal; †Department of Family and Community Medicine and Centre for Urban Health Solutions, Li Ka Shing Knowledge Institute, St. Michael's Hospital; ‡ Department of Family and Community Medicine and Dalla Lana School of Public Health, University of Toronto, Toronto; § Department of Family Medicine, McGill University; ¶ Département de Microbiologie et Infectiologie, Centre Hospitalier de l'Université de Montréal; ∥ Département de Microbiologie et Immunologie, Université de Montréal; and **Department of Epidemiology, Biostatistics and Occupational Health, McGill University, Montréal, Canada.
Sex Transm Dis. 2017 Jun;44(6):329-337. doi: 10.1097/OLQ.0000000000000612.
Assortative sexual mixing, the tendency for individuals to choose partners with similar characteristics to themselves, may be an important contributor to the unequal distribution of sexually transmitted infections in populations. We analyzed the tendency for assortative mixing on demographic and sexual behaviors characteristics in newly formed young adults dating partnerships.
Women aged 18 to 24 years and their male sexual partners of no more than 6 months were recruited during 2005 to 2010 at universities in Montreal, Canada. New dating partners were also prospectively recruited during the 2-year follow-up. We used Spearman and Newman coefficients to examine correlations between partners' demographic characteristics and sexual behaviors, and multivariable logistic modeling to determine which characteristics were assortative.
Participants in 502 recruited partnerships were assortative on age (Spearman P = 0.60), smoking behavior (P = 0.43), ethnicity (Newman coefficient=0.39), lifetime number of sexual partners (P = 0.36), sex partner acquisition rates (P = 0.22), gap length between partnerships (P = 0.20), and on whether they had concurrent partners (P = 0.33). Partners were assortative on number of lifetime partners, sexual partner acquisition rates, concurrency, and gap length between partnerships even after adjustment for demographic characteristics. Reported condom use was correlated between initial and subsequently recruited partners (P = 0.35). There was little correlation between the frequencies of vaginal/oral/digital/anal sex between subsequent partnerships.
Dating partnerships were substantially assortative on various sexual behaviors as well as demographic characteristics. Though not a representative population sample, our recruitment of relatively new partnerships reduces survivor bias inherent to cross-sectional surveys where stable long-term partnerships are more likely to be sampled.
选择性伴侣时倾向于选择与自己具有相似特征的人，即选型性混合，这可能是导致性传播感染在人群中分布不均的一个重要因素。我们分析了新形成的年轻情侣关系中在人口统计学和性行为特征方面的选型混合倾向。
2005年至2010年期间，在加拿大蒙特利尔的大学招募了年龄在18至24岁的女性及其交往不超过6个月的男性性伴侣。在为期2年的随访期间，还前瞻性地招募了新的情侣。我们使用斯皮尔曼系数和纽曼系数来检验伴侣的人口统计学特征与性行为之间的相关性，并使用多变量逻辑模型来确定哪些特征是选型性的。
在招募的502对情侣中，伴侣在年龄（斯皮尔曼P = 0.60）、吸烟行为（P = 0.43）、种族（纽曼系数 = 0.39）、终身性伴侣数量（P = 0.36）、性伴侣获得率（P = 0.22）、恋爱关系间隔时长（P = 0.20）以及是否有同时交往的伴侣（P = 0.33）方面存在选型性。即使在对人口统计学特征进行调整后，伴侣在终身伴侣数量、性伴侣获得率、同时交往情况以及恋爱关系间隔时长方面仍存在选型性。最初和后续招募的伴侣之间报告的避孕套使用情况具有相关性（P = 0.35）。后续恋爱关系中阴道/口交/指交/肛交的频率之间几乎没有相关性。
恋爱关系在各种性行为以及人口统计学特征方面存在显著的选型性。尽管我们的样本并非具有代表性的人群样本，但我们对相对新形成的恋爱关系的招募减少了横断面调查中固有的幸存者偏差，在横断面调查中更有可能抽取到稳定的长期恋爱关系。
