The present study aims to explore differences between lone, duo and 3+ group sexual aggressions by adult strangers from a Spanish sample based on victims' and offenders' socio-demographic characteristics and sexual offences. Additionally, the study aims to provide evidence of whether duo offences should be considered a different category that MPR and whether we can differentiate them from lone and 3+ group offenders. A sample of 400 sexual stranger offenders whose victims were women over 13 years of age has been analysed to find differences and predictive variables for lone (N = 298), duo (N = 43) and 3+ group (N = 59) sexual aggressions. Kruskal–Wallis tests and chi-squared analysis were used to compare the three groups and then multinomial logistic regression analysis were conducted to identify the predictive variables of group size. Results support previous studies comparing group sexual offences by its size; and that duos could be a singular category with more similarities with multiple perpetrator rape offences (age and ethnicity of offenders, similar violent control and sexual behaviour during the aggression). Some singularities have also been encountered, such as higher levels of alcohol and drug use of the perpetrators; severe consequences of their actions with more injuries to their victims; use of weapons; and less use of vehicles, which can be related to crime locations that are rarely outdoors.

中文翻译：

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多人性侵犯的参与者人数

本研究旨在根据受害者和罪犯的社会人口特征和性犯罪，从西班牙样本中探讨成年陌生人对单独、双人和 3 人以上群体性侵犯之间的差异。此外，该研究旨在提供证据，证明双人犯罪是否应被视为与 MPR 不同的类别，以及我们是否可以将其与单独和 3 人以上的团体犯罪者区分开来。分析了 400 名性陌生人犯罪者的样本，其受害者是 13 岁以上的女性，以找出单独（N  = 298）、二人组（N  = 43）和 3+ 组（N = 59) 性侵犯。Kruskal-Wallis 检验和卡方分析用于比较三组，然后进行多项逻辑回归分析以确定组大小的预测变量。结果支持以前的研究按规模比较群体性犯罪；并且二重奏可能是一个单一的类别，与多名强奸犯有更多相似之处（罪犯的年龄和种族，侵略期间类似的暴力控制和性行为）。还遇到了一些奇点，例如肇事者酗酒和吸毒的程度更高；他们的行为造成严重后果，对受害者造成更多伤害；使用武器；较少使用车辆，这可能与很少在室外的犯罪地点有关。