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Violence Research Centre


Happy New Year from the VRC! Here is a selection of published papers by members of our team and affiliated researchers in the UK and abroad. These are stored in the University of Cambridge’s Apollo repository.



Doing research with police elites in Ghana - Sowatey, E., & Tankebe, J. (2019)


Much of our methodological insights from research on policing in sub-Saharan Africa come from studies of frontline officers. Consequently, many important methodological questions about research on senior police officers remain unanswered. This article addresses this gap by drawing on insights from interviewing senior officers in Ghana. It focuses on the challenges and opportunities in negotiating access, establishing trust during interviews, and dealing with ethical dilemmas. We highlight the role of informal social networks and cultural practices of surprised visits, what we termed strategic ambush, in securing formal approval for our research. However, this represented mere or putative access for which deference towards institutional gatekeepers was key to its actualisation. Deference towards officers and extensive knowledge of the policing environment helped to put the senior officers at ease, and enhanced the chances of a successful interview. Finally, we offer reflections on our responses to unexpected ethical dilemmas we faced in the field. Download at


Violence prevention 

What can we do to reduce disciplinary school exclusion? A systematic review and meta-analysis - Sara Valdebenito & Manuel Eisner & David P. Farrington & Maria M. Ttofi & Alex Sutherland (2019)


Objectives To systematically review and quantitatively synthesise the evidence for the impact of different types of school-based interventions on the reduction of school exclusion. Methods A systematic search of 27 databases including published and unpublished literature was carried out between September and December 2015. Eligible studies evaluated interventions intended to reduce the rates of exclusion, targeted children from ages four to 18 in mainstream schools, and reported results of interventions delivered from 1980 onwards. Only randomised controlled trials were included. Two independent reviewers determined study eligibility, extracted data, and rated the methodological quality of studies. Results Based on the 37 studies eligible for meta-analysis, under a random effects model, results showed that school-based interventions significantly reduced school exclusion during the first 6 months after implementation SMD = .30, 95% CI [.20, .41], p < .001. The impact at follow-up (i.e. 12 or more months) was reduced by half and it was not statistically significant. Heterogeneity was mainly explained by the role of the evaluator: independent evaluators reported lower effect sizes than researchers involved in the design and/or delivery of the intervention. Four approaches presented promising and significant results in reducing exclusion: enhancement of academic skills, counselling, mentoring/monitoring, and skills training for teachers. Conclusions Results suggest that school-based interventions can be effective in reducing school exclusion in the short term. Some specific types of interventions show more promising and stable results, but, based on the small number of studies involved in our calculations, we suggest that results are interpreted with caution. Download at


Quantifying the Strength of General Factors in Psychopathology: A Comparison of CFA with Maximum Likelihood Estimation, BSEM, and ESEM/EFA Bifactor Approaches - Murray, A., Booth, T., Eisner, M., Obsuth, I., & Ribeaud, D. (2019)


Whether or not importance should be placed on an all-encompassing general factor of psychopathology (or p-factor) in classifying, researching, diagnosing and treating psychiatric disorders depends (amongst other issues) on the extent to which co-morbidity is symptom-general rather than staying largely within the confines of narrower trans-diagnostic factors such as internalising and externalising. In this study we compared three methods of estimating p-factor strength. We compared omega hierarchical and ECV calculated from CFA bi-factor models with maximum likelihood (ML) estimation, from ESEM/EFA models with a bifactor rotation, and from BSEM bi-factor models. Our simulation results suggested that BSEM with small variance priors on secondary may be the preferred option. However, CFA with ML also performed well provided secondary loadings were modelled We provide two empirical examples of applying the three methodologies using a normative sample of youth (z-proso, n=1286) and University counselling sample (n= 359). Download at


Delivering a Parenting Program in South Africa: The Impact of Implementation on Outcomes - Shenderovich, Y., Eisner, M., Cluver, L., Doubt, J., Berezin, M., Majokweni, S., & Murray, A. (2019)


Objectives: Previous studies of parenting programs suggest that facilitator fidelity, participant attendance and engagement often influence treatment outcomes. While the number of parenting program evaluations has been growing in low- and middle-income countries, little is known about the implementation processes and their impact on participant outcomes in these settings. Methods: This study was nested within a cluster-randomised trial of a parenting program in South Africa. The paper aims to, first, describe the implementation of the intervention over 14 weeks. Second, using longitudinal multilevel analyses, the paper examines the impact of variation in observer-rated fidelity, attendance, and engagement on participant outcomes – parenting and maltreatment reported by caregivers and adolescents aged 10-18 (N=270 pairs), 14 outcome constructs. Results: Fidelity, attendance and participant engagement rates were similar to those reported in high-income country studies. However, the participation and implementation characteristics did not predict participant outcomes. This may be due to limited variation in dosage as home visits were comprehensively provided when participants could not attend group sessions, and fidelity was monitored by the implementers and researchers. One statistically significant predictor after the multiple testing correction was higher fidelity predicting an increase in adolescent-reported maltreatment at follow-up, possibly due to an increase in reporting (incidence rate ratio 1.33, 95% CI [1.19, 1.49], p<0.01). Conclusions: Our study confirms that a high quality of implementation can be achieved in a low-resource context. Suggestions for future research on parenting programs include examining therapeutic alliance alongside program fidelity and facilitator skill as well as systematically recording program adaptations. Download at


Sex Trade among Youth: A Global Review of the Prevalence, Contexts and Correlates of Transactional Sex among the General Population of Youth - Krisch, M., Averdijk, M., Valdebenito, S., & Eisner, M. (2019)


Transactional sex, the casual exchange of sexual favors for money or gifts, has been associated with negative outcomes and health risks, particularly among youth. This global review of the evidence explores trends of buying and selling of sex among the general population of male and female youth across 28 countries. It compares the differences and similarities in prevalence rates between genders (male versus female), sex trading activities (selling versus buying), and country income groups (high-income versus low and middle-income countries) and examines the relationships and situations surrounding transactional sex, and its correlates. The screening of reports resulted in the inclusion of 37 manuscripts (N=120,447 participants), involving peer review and grey literature describing longitudinal and cross-sectional research across 7 high-income and 21 low- and middle-income countries. The review of prevalence rates suggests relatively low rates of transactional sex in high-income countries (with selling and buying rates below 10% in all countries) and relatively high, although varying rates, in low- and middle-income countries (with selling and buying rates of 60% or higher in 7 countries). Gender disaggregated data suggests that boys are more likely than girls to sell sex in high-income countries while the opposite seems to be true in low- and middle-income countries. The findings suggest that initial contact between sellers and buyers is most often established through friends, acquaintances, and dating websites. The age of onset is around 15 years, many sellers and buyers already know each other before trading sex, and they are often of a similar age. Money is the most commonly used form of compensation. Correlates of selling sex include involvement in other risky sexual behaviors, substance use, infection with sexually transmitted diseases, mental health problems, family break-up, and a history of victimization. No or mixed relations have been found with socioeconomic and educational status. The correlates of buying sex include promiscuity, substance use, violence perpetration and, to some extent, higher socioeconomic status. Recommendations for future research are discussed. Download at




Centrality, Mobility, and Specialization: A Study of Drug Markets in a Non-metropolitan Area in the United Kingdom - Baika, L., & Campana, P. (2019) 


This paper empirically explores the structure and mechanisms underpinning the local drug markets in a non-metropolitan area in the United Kingdom. It relies on three years’ worth of police records supplemented with qualitative evidence. It shows that, overall, supplying drugs is a rather fragmented business, yet there are indications of structural differentiation both in terms of positions and roles. Further, substantial differences emerge across drug types – with heroin and cocaine networks showing a higher tendency towards cooperation and group formation (higher average degree and lower fragmentation). This might be due to a higher need for protection and more complex supply chains. Drug suppliers tend to specialise in relation to the Class A drugs, their role in the market and the territory in which they operate. Finally, members of organised crime groups possess significantly higher degree centrality than non-members, suggesting an ability to exert influence on the market. Download at ttps://


Picture: Anna Samoylova, CC





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