BackgroundNumerous studies have established that crime is highly concentrated among a small group of offenders. These findings have guided the development of various crime prevention strategies. The underlying theme of these strategies is that by focusing on the few offenders who are responsible for most of the crime, we can prevent the greatest amount of crime with the fewest resources. Nevertheless, there has been no systematic review of the many studies, so it is possible that the accepted understanding among researchers and practitioners is based on a few prominent studies that are misleading. Further, we do not know how concentrated crime is among offenders, given the variety of ways researchers report their findings. This paper systematically reviews this literature and uses meta-analysis to determine how confident we can be that crime is concentrated among a few offenders.MethodsWe first systematically reviewed the literature and found 73 studies on the concentration of crime among offenders. From those studies, we identified 15 studies on the prevalence of offending and 27 studies on the frequency of offending that provided data suitable for analysis. We then performed a meta-analysis of those studies to examine how crime is concentrated among the worst offenders and how that concentration varies between different types of offenders.ResultsWe found that crime is highly concentrated in the population and across different types of offenders. Little variation in concentration exists between youths and adults or between American offenders and those from other countries. We found more variation between males and females in the concentration of offending, though we believe this may be due to the more limited data on female offenders.ConclusionsThe systematic review and meta-analysis we present here is the first study of its kind on offending concentration. This is an important step in closing this gap in the crime prevention literature, but we encourage making updates to this systematic review as new literature becomes available, and using alternate methods of summarizing these studies that could challenge these findings.

中文翻译：

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再谈狼：对犯罪集中的系统回顾

背景技术大量研究表明，犯罪高度集中在一小群罪犯中。这些发现指导了各种犯罪预防策略的发展。这些策略的基本主题是，通过集中精力应对大多数犯罪负责的少数犯罪者，我们可以用最少的资源来预防最多的犯罪。然而，许多研究尚未得到系统的审查，因此研究人员和从业人员公认的理解可能是基于一些具有误导性的著名研究。此外，鉴于研究人员报告其调查结果的方式多种多样，我们不知道犯罪者中犯罪的集中度如何。本文系统地回顾了这些文献，并使用荟萃分析来确定我们对犯罪集中在少数罪犯中的信心有多强。从这些研究中，我们确定了15项关于犯罪发生率的研究和27项关于犯罪发生频率的研究，这些研究提供了适合分析的数据。然后，我们对这些研究进行了荟萃分析，以研究犯罪如何集中在最严重的犯罪者中以及犯罪类型在不同类型的犯罪者之间如何变化。结果我们发现犯罪高度集中于人口和不同类型的犯罪者中。青年和成年人之间或美国犯罪者与其他国家犯罪者之间的集中度几乎没有差异。尽管我们认为这可能是由于女性罪犯的数据有限所致，但我们发现男性和女性在犯罪集中度方面的差异更大。结论我们在此进行的系统综述和荟萃分析是此类研究中关于犯罪浓度的首次研究。这是弥合预防犯罪文献中这一空白的重要一步，但是我们鼓励随着新文献的出现，对本系统综述进行更新，并使用其他汇总这些研究的方法来挑战这些发现。尽管我们认为这可能是由于女性罪犯的数据有限所致。结论我们在此进行的系统综述和荟萃分析是该类犯罪集中度的首次研究。这是弥合预防犯罪文献中这一空白的重要一步，但是我们鼓励随着新文献的出现，对本系统综述进行更新，并使用其他汇总这些研究的方法来挑战这些发现。尽管我们认为这可能是由于女性罪犯的数据有限所致。结论我们在此进行的系统综述和荟萃分析是该类犯罪集中度的首次研究。这是弥合预防犯罪文献中这一空白的重要一步，但是我们鼓励随着新文献的出现，对本系统综述进行更新，并使用其他汇总这些研究的方法来挑战这些发现。