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Search Result: 48 Records found
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The promotion of well-being among children exposed to intimate partner violence
  • Authors Natasha E. Latzman, Cecilia Casanueva, Julia Brinton, Valerie L. Forman-Hoffman
  • Published date 2019-09-30
  • Coordinating group(s) Crime and Justice, Social Welfare
  • Type of document Review Plain language summary
  • Title The promotion of well-being among children exposed to intimate partner violence
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/full/10.1002/cl2.1049
  • English

    PLAIN LANGUAGE SUMMARY

    Limited evidence on the effectiveness of psychosocial interventions to promote well-being among children exposed to intimate partner violence

    Children’s exposure to intimate partner violence (IPV) is a significant public health and social justice concern with potentially severe and long-lasting effects. The extent to which psychosocial interventions promote well-being among children exposed to IPV, and under what circumstances, such as the modality and setting, is unclear.

    What is this review about?

    Exposure to IPV in childhood can have both short- and long-term negative impacts to health and well-being that persist across generations. There is therefore an increased interest in the development of intervention strategies to promote well-being following exposure. Over the last two decades, theory-driven psychosocial programmes serving children exposed to violence have been developed and established in a range of venues (e.g., school-based mental health clinics, outpatient psychotherapy settings). This review provides a synthesis of the state of this literature and implications for research and practice.

    Specifically, the effectiveness of psychosocial interventions in improving total problems, externalising distress, internalising distress, interpersonal/social problems, and cognitive functioning are assessed. Variation in effects by intervention modality (e.g., individual, family-based) and setting of the intervention (e.g., home, outpatient clinic) are also examined.

    What is the aim of this review?

    This Campbell systematic review examines the effects of psychosocial interventions to promote well-being among children exposed to intimate partner violence. The review summarizes evidence from eight methodologically rigorous randomized controlled trials.

    What studies are included?

    This review includes eight randomised controlled trials (RCTs), with a total of 924 participants.

    The majority of studies were conducted in the USA, with one study each carried out in the Netherlands and India. The age range of target children varied, although all fell within the age range of 0 to 18 years.

    Three of the studies recruited general populations of parents and/or children who had been exposed to IPV, without stated inclusion criteria around parent or child symptomatology or functioning.

    Four studies had more explicit inclusion requirements such as children with IPV-related post-traumatic stress disorder (PTSD) symptoms and fathers with alcohol dependence. Studies varied widely regarding the nature of IPV experienced by parents and witnessed or heard by children.

    What are the main findings of this review?

    Studies examined following outcomes: total problems, externalising distress, internalising distress, interpersonal/social problems, and cognitive functioning. However, differences in the specific measures used, interventions employed, and comparison groups limit the ability to synthesize findings.

    Evidence from two studies suggests there is preliminary evidence that in-home intensive services (parent training and provision of emotional support to the parent) decreases child externalising behaviour among children who have been exposed to IPV and have clinical levels of behaviour problems. However, support for this evidence was only found immediately post-treatment and at an eight-month follow-up, but not at a four-month follow-up.

    Intervention targeting the non-offending parent (mother) had the largest effect, followed by those that targeted the family together and, finally, the single study that targeted parent and child, separately.

    Interventions conducted in the home had a larger effect compared to those conducted in an outpatient setting. However, these findings should be interpreted with great caution due to the heterogeneity in study characteristics such as the nature of the comparators.

    Overall, it is largely unclear the extent to which psychosocial interventions promote well-being among children exposed to IPV, and under what circumstances.

    What do the findings of the review mean?

    The findings from this systematic review indicate that it is largely unclear the extent to which psychosocial interventions promote well-being among children exposed to IPV, and under what circumstances.

    More rigorous evaluation of psychosocial interventions needs to be conducted using common outcomes across studies in order to draw conclusions. We suggest that in addition to increased rigour in evaluation design (such as efforts to minimise selection bias), researchers assess the nature of child exposure and multiple subtypes of IPV; this will help elucidate whether interventions are more or less effective depending on the IPV exposure context.

    How up-to-date is this review?

    The review authors searched for studies up to April 2018.

Focused deterrence strategies effects on crime
  • Authors Anthony A. Braga, David L. Weisburd, Brandon Turchan
  • Published date 2019-09-09
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Focused deterrence strategies effects on crime
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/full/10.1002/cl2.1051
  • English

    PLAIN LANGUAGE SUMMARY

    Focused deterrence is associated with moderate reductions in crime

    A relatively small number of groups and persons are responsible for a disproportionate share of crime. Focused deterrence strategies attempt to reduce offending behaviour for specific types of crime. These strategies are associated with moderate overall reductions in crime.

    Crime is not displaced to other areas, rather it is more likely that there is a diffusion of crime control benefits to adjacent areas and similar people and groups.

    What is this review about?

    Focused deterrence strategies combine law enforcement, community mobilisation, and social services in an attempt to reduce offending behaviour for specific crime types. A key feature of this crime control strategy is that the consequences of continued criminal offending and available social services are directly communicated to targeted subjects.

    This review examines the relationship between focused deterrence policing and crime, and gives consideration to the different types of focused deterrence strategies and programme evaluation designs.

    What is the aim of this review?

    This Campbell systematic review examines the effects of focused deterrence policing on crime. The review summarises and analyses results from 24 quasi-experimental evaluations of focused deterrence interventions, including 12 programmes targeting criminally active gangs or groups, nine programmes targeting open-air drug markets, and three programmes targeting high-risk individual offenders. All but one of the studies are from the USA.

    What studies are included?

    A total of 24 studies of focused deterrence policing interventions were identified. All studies were published from 2001 to 2015. Twenty-three studies were conducted in the USA and one in Scotland. None of the identified studies used a randomised controlled trial design.

    What are the main findings of this review?

    Is focused deterrence an effective approach to reducing criminal offending among problem persons and groups?

    Yes. The available evidence suggests an overall reduction in crime when focused deterrence strategies are used. The largest reductions are generated by focused deterrence programmes that target criminally active gangs or groups, followed by interventions that target chronic individual offenders and drug market interventions.

    Do some programmes work better than others?

    Yes. Gang/group intervention programmes have the largest effect, followed by the high-risk individuals programmes, with the smallest effect from drug market intervention (DMI) programmes. DMI programmes are most likely to suffer implementation problems, which reduce effectiveness.

    Does crime get displaced to other areas?

    No. No studies found significant crime displacement effects into surrounding areas. There is some evidence of the diffusion of crime control benefits.

    What do the findings of the review mean?

    Findings from this review support the growing use of focused deterrence as a proactive crime reduction strategy. Practitioners and policymakers should continue to implement focused deterrence programmes to address serious crime problems.

    The number of studies included in the updated review is more than double the number of studies included in the previous iteration of the review. However, despite the increase in eligible studies, no evaluations utilised a randomised controlled trial design. The growth of focused deterrence warrants more methodologically rigorous programme evaluations and further exploration into the specific components of the strategy, to improve our understanding into how the programme reduces crime.

    How up-to-date is this review?

    The review authors searched for studies up to October 2015.

Disorder policing to reduce crime
  • Authors Anthony Braga, Brandon Welsh, Cory Schnell
  • Published date 2019-09-09
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Disorder policing to reduce crime
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.1002/cl2.1050
  • English

    PLAIN LANGUAGE SUMMARY

    Policing disorder through community and problem-solving policing is associated with reductions in crime, but aggressive, order maintenance approaches are not

    Disorderly conditions are seen as a precursor to more serious crime, fear of crime, and neighbourhood decline. Policing disorder is associated with reductions in crime, but only when community and problem-solving tactics are used. Aggressive, order maintenance based approaches are not effective.

    What is the aim of this review?

    This Campbell systematic review examines the effects of disorder policing interventions on crime. The review summarises evidence from 28 high-quality studies (representing 30 independent tests), including nine randomised controlled trials. Most the studies come from the USA.

    What is this review about?

    Policing social and physical disorderly conditions is rooted in the broken windows approach: disorder is a precursor to more serious crime, fear of crime, and neighborhood decline. Addressing disorder has become a central fixture of policing, especially in the USA. Yet, evaluations of the effectiveness of disorder policing strategies in controlling crime yield conflicting results.

    Policing disorderly conditions can be divided into two main strategies: (1) Order maintenance or zero tolerance policing, where police attempt to impose order through strict enforcement; and (2) Community policing and problem-solving policing, where police attempt to produce order and reduce crime through cooperation with community members and by addressing specific recurring problems.

    This review examined the effects of disorder policing strategies compared to traditional law enforcement actions (e.g., regular levels of patrol) on the rates of crime, including property crime, violent crime, and disorder/drug crime. This review also examined whether policing disorder actions at specific locations result in crime displacement (i.e., crime moving around the corner) or diffusion of crime control benefits (i.e., crime reduction in surrounding areas).

    What studies are included?

    A total of 28 disorder policing studies (representing 30 independent tests) met the criteria to be included in this review. The studies spanned the period from 1985 to 2012, and were mostly carried out in the USA. All of the studies used high-quality designs to evaluate the impact of the intervention; nine were randomised controlled trials. Twelve tests were completed in large cities (more than 500,000 residents), nine tests were completed in medium-sized cities (200,000 to 500,000 residents), and the other nine tests were completed in smaller cities. All of the tests were carried out in specific geographical settings, including small places (e.g., crime hot spots and problem buildings), smaller police-defined areas (e.g., patrol beats), neighbourhoods and selected stretches of highways, and larger police-defined areas (e.g., precincts and divisions).

    What are the main findings of this review?

    Do policing interventions focused on disorderly conditions reduce crime?

    Yes, in addition to an overall reduction in crime, there is a reduction in property crime, violent crime, and disorder/drug crime when disorder policing interventions are implemented.

    Do policing interventions focused on disorder result in crime being displaced or crime control benefits being diffused to surrounding areas?

    Disorder policing interventions are associated with diffusion of crime control benefits in areas surrounding targeted locations. This conclusion is based on 15 tests that measured displacement or diffusion effects.

    Of the two main strategies used in policing disorder, is one more effective than the other?

    Yes, policing disorder through community and problem-solving is associated with reductions in crime. Aggressive, order maintenance approaches are not effective.

    What do the findings of the review mean?

    The types of strategies used by police departments to address disorderly conditions seem to matter in controlling crime, and this holds important implications for police-community relations, justice, and crime prevention. Further research is needed to understand the key programmatic elements that maximise the capacity of these strategies

    How up-to-date is this review?

    This review includes studies completed before 2013.

Hot spots policing of small geographic areas effects on crime
  • Authors Anthony A. Braga, Brandon Turchan, Andrew V. Papachristos, David M. Hureau
  • Published date 2019-09-08
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Hot spots policing of small geographic areas effects on crime
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/full/10.1002/cl2.1046
  • English

    PLAIN LANGUAGE SUMMARY

    Hot spots policing is associated with reductions in crime

    Hot spots policing is associated with small but meaningful reductions in crime at locations where criminal activities are most concentrated. Focusing police efforts at high activity crime places is more likely to produce a diffusion of crime prevention benefits into areas adjacent to targeted hot spots than crime displacement.

    What is this review about?

    Crime is concentrated in small places, or "hot spots," that generate half of all criminal events. Hot spots policing focuses police resources and attention on these high crime places. For the purpose of this review, hot spots programs must have consisted of police-led crime prevention efforts that targeted high-activity crime "places" rather than larger areas such as neighborhoods.

    This review considers both randomized controlled experimental and quasi-experimental evaluations of the effects of hot spots policing interventions on crime where the control group in each study received routine levels of traditional police enforcement tactics.

    What is the aim of this review?

    This Campbell systematic review assesses the preventive effects of focusing police efforts on crime "hot spots" as compared to traditional police crime control strategies.  The review summarises evidence from 65 studies containing 78 tests of hot spots policing interventions, including 27 randomized controlled trials and 38 quasi-experimental evaluations.

    What studies are included?

    A total of 65 studies containing 78 tests of hot spots policing interventions were identified. However, standardized effects sizes were only calculated for 73 main effects tests due to reporting deficiencies in three included studies.

    All studies were published from 1989 to 2017: 51 studies were conducted in the USA, four in the UK, four in Sweden, and six in other countries.

    What are the main findings of this review?

    Does focusing crime prevention efforts on crime hot spots reduce crime?

    Yes. Hot spots policing generates statistically-significant small reductions in overall crime and disorder in areas where the strategy is implemented.

    These crime control gains were evident across specific categories of crime outcomes including drug offenses, disorder offenses, property crimes, and violent crimes.

    Does policing crime hot spots inevitably produce crime displacement effects?

    No. Overall, it is more likely that hot spots policing generates crime control benefits that diffuse into the areas immediately surrounding the targeted locations than displacing crime into nearby locations.

    What do the findings of the review mean?

    Findings from this review support hot spots policing as a proactive crime reduction strategy. Police departments should incorporate focusing resources at high-activity crime places as part of their broader approach to crime prevention.

    The majority of studies included in the updated review have been published since the previous iteration of the review and utilized rigorous research designs.

    Despite the drastic increase in eligible studies, only one study conducted a formal cost-benefit assessment of the hot spot policing intervention. The growth of hot spots policing warrants further empirical attention on the efficiency of hot spots policing for reducing crime.

    How up-to-date is this review?

    The review authors searched for studies up to February 2017.

Cognitive-behavioural treatment for amphetamine-type stimulants (ATS)-use disorders
  • Authors Takayuki Harada, Hiroshi Tsutomi, Rintaro Mori, David Wilson
  • Published date 2019-07-25
  • Coordinating group(s) Crime and Justice
  • Type of document Review
  • Title Cognitive-behavioural treatment for amphetamine-type stimulants (ATS)-use disorders
  • See the full review https://onlinelibrary.wiley.com/doi/10.1002/cl2.1026
  • English

    PLAIN LANGUAGE SUMMARY

    Cognitive‐behavioural treatment for amphetamine‐type stimulants‐use disorders

    What was the aim of this review?

    The aim of this Cochrane review was to find out whether cognitive‐behavioural treatment (CBT) is effective to treat people with amphetamine‐type stimulants (ATS)‐use disorders. Researchers in the Drugs and Alcohol Group of Cochrane collected and analysed all relevant studies to answer this question and found two studies.

    Key messages

    The current evidence was inadequate to draw any firm evidence‐based treatment recommendations for the client population.

    What was studied in the review?

    ATS are a group of synthetic stimulants and their use has been widespread globally. These types of drugs are highly addictive and prolonged use may result in a series of mental and physical symptoms including anxiety, confusion, insomnia (difficulty sleeping), mood disturbances, cognitive impairments (difficulty thinking and understanding), paranoia (irrational feeling that people are 'out to get you'), hallucinations (where someone experiences something that does not exist outside their own mind) and delusion (a mistaken belief).

    Currently there is no widely accepted treatment for ATS‐use disorder. However, CBT is often the first choice of treatment. It is a psychological treatment (talking therapy) approach to modify distorted thoughts and beliefs, and maladaptive behaviours (things that people do to stop them from adjusting to situations). The effectiveness of CBT for other substance‐use disorders (e.g. alcohol‐, opioid‐ and cocaine‐use disorders) has been well documented and as such this basic treatment approach has been applied to the ATS‐use disorder. These types of therapies are expected to prevent relapse and decrease drug use.

    What are the main results of the review?

    The review authors found two eligible studies. Both studies were conducted in Australia. One study compared a single session of brief CBT to a waiting‐list control where participants received no treatment during the study period. One study compared web‐based CBT to a waiting‐list control. Both studies were funded by the Australian Government of Health and Ageing.

    The review showed that when participants received CBT, compared to waiting‐list control, there was no difference. There was insufficient evidence to conclude that CBT was effective or ineffective at treating ATS‐use disorders.

    How up‐to‐date is this review

    The review authors searched for studies that had been published up to July 2018.

Effects of bystander programs on the prevention of sexual assault among adolescents and college students
  • Authors Heather Hensman Kettrey, Robert A. Marx, Emily E. Tanner-Smith
  • Published date 2019-01-04
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Effects of bystander programs on the prevention of sexual assault among adolescents and college students
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2019.1
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Bystander programs increase bystander intervention but no effect on perpetrating sexual assault

    Bystander sexual assault prevention programs have beneficial effects on bystander intervention but there is no evidence of effects on sexual assault perpetration. Effects on knowledge and attitudes are inconsistent across outcomes.

    What is this review about?

    Sexual assault is a significant problem among adolescents and college students across the world. One promising strategy for preventing these assaults is the implementation of bystander sexual assault prevention programs, which encourage young people to intervene when witnessing incidents or warning signs of sexual assault. This review examines the effects bystander programs have on knowledge and attitudes concerning sexual assault and bystander behavior, bystander intervention when witnessing sexual assault or its warning signs, and participants’ rates of perpetration of sexual assault.

    What is the aim of this review?

    This Campbell systematic review examines the effects of bystander programs on knowledge and attitudes concerning sexual assault and bystander intervention, bystander intervention when witnessing sexual assault or its warning signs, and the perpetration of sexual assault. The review summarizes evidence from 27 high‐quality studies, including 21 randomized controlled trials.

    What studies are included?

    This review includes studies that evaluate the effects of bystander programs for young people on (a) knowledge and attitudes concerning sexual assault and bystander intervention, (b) bystander intervention behavior when witnessing sexual assault or its warning signs, and (c) perpetration of sexual assault. Twenty‐seven studies met the inclusion criteria. These included studies span the period from 1997 to 2017 and were primarily conducted in the USA (one study was conducted in Canada and one in India). Twenty‐one studies were randomized controlled trials and six were high quality quasi‐experimental studies.

    What are the main findings of this review?

    Do bystander programs have an effect on knowledge/attitudes, on bystander intervention, or on sexual assault perpetration?

    Bystander programs have an effect on knowledge and attitudes for some outcomes. The most pronounced beneficial effects are on rape myth acceptance and bystander efficacy outcomes. There are also delayed effects (i.e., 1 to 4 months after the intervention) on taking responsibility for intervening/acting, knowing strategies for intervening, and intentions to intervene outcomes. There is little or no evidence of effects on gender attitudes, victim empathy, date rape attitudes, and on noticing sexual assault outcomes.

    Bystander programs have a beneficial effect on bystander intervention. There is no evidence that bystander programs have an effect on participants’ rates of sexual assault perpetration.

    What do the findings of this review mean?

    The United States 2013 Campus Sexual Violence Elimination (SaVE) Act requires postsecondary educational institutions participating in Title IX financial aid programs to provide incoming college students with sexual violence prevention programming that includes a component on bystander intervention.

    Bystander programs have a significant effect on bystander intervention. But there is no evidence that these programs have an effect on rates of sexual assault perpetration. This suggests that bystander programs may be appropriate for targeting the behavior of potential bystanders but may not be appropriate for targeting the behavior of potential perpetrators.

    Beneficial effects of bystander programs on bystander intervention were diminished by 6 months post‐intervention. Thus, booster sessions may be needed to yield any sustained effects.

    There are still important questions worth further exploration. Namely, more research is needed to investigate the underlying causal mechanisms of program effects on bystander behavior (e.g., to model relationships between specific knowledge/attitude effects and bystander intervention effects), and to identify the most effective types of bystander programs (e.g., using randomized controlled trials to compare the effects of two alternate program models). Additionally, more research is needed in contexts outside of the USA so that researchers can better understand the role of bystander programs across the world.

    How up‐to‐date is this review?

    The review authors searched for studies up to June 2017.

  • Spanish

    RESUMEN EN LENGUAJE SENCILLO

    Los programas contra la omisión de socorro para transeúntes aumentan su intervención, pero no afectan la incidencia de las agresiones sexuales

    Los programas de prevención de agresiones sexuales para crear conciencia en los transeúntes acerca de la omisión de socorro tienen efectos positivos en cuanto a la intervención de los mismos, aunque no existe evidencia que muestre impacto alguno en la incidencia sobre las agresiones sexuales. Los efectos en el conocimiento y las actitudes son contradictorias en todos los resultados.

    ¿Qué estudió la revisión?

    Las agresiones sexuales son un gran problema entre adolescentes y estudiantes universitarios en todo el mundo. Una estrategia prometedora para prevenir estas agresiones es la implementación de programas de prevención de agresiones sexuales para educar a transeúntes, que fomenten a los jóvenes a intervenir cuando sean testigos de este tipo de incidentes o adviertan señales de que existe algún tipo de agresión sexual. Esta revisión examina los efectos que los programas contra la omisión de socorro para transeúntes tienen en cuanto al conocimiento y las actitudes relacionadas con las agresiones sexuales, el comportamiento de los transeúntes, su intervención al momento de presenciar una agresión sexual o sus señales de advertencia, y las tasas de participación en la comisión de agresiones sexuales.

    ¿Cuál es el objetivo de esta revisión?

    Esta revisión sistemática Campbell examina los efectos de los programas de transeúntes en cuanto al conocimiento y las actitudes relacionadas con las agresiones sexuales y la intervención de transeúntes, su intervención cuando presencian una agresión sexual o sus señales de advertencia, y la comisión de agresiones sexuales. Esta revisión resume evidencia de 27 estudios de alta calidad, incluyendo 21 ensayos de control aleatorizados.

    ¿Qué estudios se incluyen?

    Esta revisión incluye estudios que evalúan los efectos de los programas de transeúntes para jóvenes en cuanto a (1) su conocimiento y las actitudes relacionadas con las agresiones sexuales, y la capacidad de intervención del transeúnte, (2) el ímpetu de los transeúntes a intervenir cuando son testigos de una agresión sexual o advierten señales de ella, y (3) la incidencia de agresiones sexuales.

    Veintisiete estudios cumplieron los criterios de inclusión. Estos estudios abarcaron el período entre 1997 y 2017 y fueron llevados a cabo principalmente en Los Estados Unidos (un estudio fue hecho en Canadá y otro en la India). Veintiún estudios fueron ensayos controlados aleatorizados y seis fueron estudios cuasi experimentales de alta calidad.

    ¿Los programas de transeúntes tienen un efecto en el conocimiento/actitudes en la intervención de peatones, o en la perpetración de un asalto sexual?

    Los programas para concientizar a los transeúntes muestran efectos en el conocimiento y las actitudes en algunos resultados.

    Los efectos más beneficiosos son que se acepte la historia contada por la víctima de la violación y los resultados en cuanto a la eficiencia de la intervención del transeúnte. También hay consecuencias diferidas (ej.: de uno a cuatro meses después de la intervención) en cuanto a asumir la responsabilidad por mediar/actuar, estar en conocimiento de estrategias de intervención y los resultados de la intención de intervenir. Existe poca o insuficiente evidencia acerca de los efectos sobre las actitudes de género, la empatía con la víctima, las actitudes de violación en citas, y en notar los efectos de las agresiones sexuales.

    Los programas de concientización de transeúntes tienen un efecto positivo en su intervención. No hay evidencia que demuestre que los programas de transeúntes afecten los índices de participación en la comisión de agresiones sexuales.

    ¿Qué significan los resultados de esta revisión?

    La ley de Eliminación de Violencia Sexual en los Campus de Estados Unidos 2013 (SaVE) procura que las instituciones educativas postsecundarias participen en el Título IX de los programas de asistencia financiera, entregando a los nuevos alumnos universitarios programas de prevención de violencia sexual, la cual incluye un componente sobre la intervención de los transeúntes.

    Los programas de concientización de transeúntes tienen un efecto significativo en su intervención. No obstante, no hay evidencia que estos programas afecten las tasas de incidencia de agresiones sexuales. Esto sugiere que los programas de transeúntes pueden ser apropiados en cuanto al comportamiento de posibles transeúntes que observen un hecho de agresión, aunque no tanto en cuanto al comportamiento de los potenciales autores del crimen.

    Los efectos positivos de los programas de transeúntes en cuanto a la intervención peatonal disminuyeron seis meses después de la intervención. De este modo, sería necesario contemplar sesiones de refuerzo para mantener los efectos de forma sostenida.

    Aún quedan preguntas importantes que requieren una exploración más profunda. Es decir, es necesario hacer más estudios que investiguen los mecanismos causales subyacentes de los efectos del programa en el comportamiento de los transeúntes (ej.: para modelar las relaciones entre los efectos de conocimiento/actitud específica y los efectos de la intervención de los peatones), e identificar los tipos de programas de transeúntes más efectivos (ej.: usar ensayos controlados aleatorizados para comparar los efectos de dos modelos de programas alternativos). Además, se necesita mayor investigación en contextos fuera de Estados Unidos para que los investigadores puedan comprender mejor el rol de los programas de transeúntes en todo el mundo.

    ¿Cuán actualizada es esta revisión?

    Los autores de la revisión buscaron estudios hasta junio de 2017. Esta revisión sistemática Campbell fue enviada en octubre de 2017, revisada en octubre de 2018 y publicada en enero de 2019.

Factors associated with youth gang membership in low- and middle-income countries
  • Authors Angela Higginson, Kathryn Benier, Yulia Shenderovich, Laura Bedford, Lorraine Mazerolle, Joseph Murray
  • Published date 2018-11-29
  • Coordinating group(s) Crime and Justice, International Development
  • Type of document Review Plain language summary
  • Title Factors associated with youth gang membership in low- and middle-income countries
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.11
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Evidence shows which factors predict gang membership in low- and middle-income countries, but more studies needed

    Youth gang membership is associated with delinquency, violent crime and trafficking. A range of individual, peer, family, school and community factors can predict the likelihood of youths getting involved with gangs. Knowledge of these factors can be helpful for reducing gang membership.

    What did the review study?

    Youth gang membership is associated with delinquency, violent crime and trafficking – and gang members are themselves frequently the victims of these offences. Yet youth gangs can also provide a form of social capital, a sense of belonging and purpose to disenfranchised youth.

    This review identifies the factors associated with young people joining gangs, and the differences between gang-involved and non- gang-involved youth. Understanding these associations is essential to reduce the levels of gang membership and the incidence of related violence.

    What is the aim of this review?

    This Campbell systematic review examines the predictors of youth gang membership in low- and middle-income countries. The review summarises findings from eight reports from five countries and the Caribbean region.

    What studies are included?

    Studies of youth gangs in in low- and middle-income countries were included, with participants aged 10-29 years. The studies had to assess an individual predictor or correlate of youth gang membership, where the predictor or correlate is a single characteristic, not a conglomeration of multiple constructs. Included studies had designs including data on both gang- involved and non-gang-involved youth, recruited with strategies that were eligible.

    Nine studies met the eligibility criteria and were included in the review. One of these studies did not report all the required data and so was not included in the analyses. The studies were conducted in Turkey, Trinidad and Tobago, the Caribbean, El Salvador, China and Brazil.

    What are the main results in this review?

    The eight studies analysed in the review address the associations between life events and circumstances, and the likelihood of being a youth gang member across five domains: individual, peers, family, school and community. Significant associations were found with factors in each domain.

    What do the findings of this review mean? The lack of available evidence limits the extent to which clear conclusions can be drawn about the factors associated with youth gang membership. The review is based on a very small number of studies, and has significant limitations in coverage. The limited evidence of the correlates of youth gang membership suggests factors that may drive gang membership and suggests areas where interventions may prove promising in the family, school, and community domains, as well as provide a starting point for future studies.

    How up-to-date is this review?

    The review authors searched for studies published up to September 2013.

  • Spanish

    RESUMEN EN LENGUAJE SENCILLO

    La evidencia resalta los factores que explican la pertenencia a pandillas en los países de ingresos medios y bajos, pero se requieren más estudios

    La pertenencia a pandillas juveniles está asociada con la delincuencia, los delitos violentos y el tráfico ilícito. Una variedad de factores individuales, de pares, familiares, escolares y comunitarios pueden predecir la probabilidad de que los jóvenes se involucren con pandillas. Conocer estos factores puede resultar útil para disminuir el ingreso de jóvenes a pandillas.

    ¿Qué estudió la revisión?

    La pertenencia a pandillas juveniles está asociada con la delincuencia, los delitos violentos y el tráfico ilícito, y los pandilleros mismos son a menudo víctimas de estos delitos. No obstante, las pandillas juveniles también pueden proveer capital social, sentido de pertenencia y un propósito para los jóvenes marginados. Esta revisión identifica los factores asociados con la afiliación de jóvenes a pandillas y las diferencias entre los jóvenes afiliados a pandillas y los no afiliados. Comprender estas relaciones es esencial para reducir los niveles de pertenencia a pandillas y la incidencia de la violencia que se relaciona con ellas.

    ¿Cuál es el objetivo de esta revisión?

    Esta revisión sistemática Campbell examina los factores predictivos de la pertenencia a pandillas juveniles en países de ingresos bajos y medios. La revisión resume las conclusiones de ocho informes de cinco países y la región del caribe.

    ¿Qué estudios se incluyen?

    Se incluyeron estudios de pandillas juveniles en países de ingresos medios y bajos, con participantes de 10 a 29 años. Los estudios debían analizar un factor predictivo o correlacionado a nivel individual con la pertenencia a pandillas juveniles, donde el factor predictivo o correlacionado fuera una característica individual y no grupos de múltiples constructos. Los estudios incluidos tenían diseños que comprendían datos acerca de jóvenes afiliados y no afiliados a pandillas, reclutados con estrategias elegibles para la inclusión.

    Nueve estudios cumplieron los criterios de elegibilidad y se incluyeron en la revisión. Uno de estos estudios no reportó todos los datos requeridos, por lo que no se incluyó en los análisis. Los estudios se realizaron en Turquía, Trinidad y Tobago, el Caribe, El Salvador, China y Brasil.

    ¿Cuáles son los principales hallazgos de esta revisión?

    Los ocho estudios analizados en la revisión abordan la relación entre las experiencias de vida y las circunstancias, con la probabilidad de pertenecer a una pandilla juvenil a lo largo de cinco esferas sociales: individual, de pares, familiar, escolar y comunitario. Se hallaron relaciones significativas con determinados factores para cada una de ellas.

    ¿Qué significan los resultados de esta revisión?

    La falta de evidencia disponible limita la medida en que se pueden extraer conclusiones claras acerca de los factores asociados con la pertenencia a pandillas juveniles. La revisión se basa en un número muy pequeño de estudios y tiene limitaciones de cobertura importantes. La evidencia sugiere que existen factores que pueden impulsar la pertenencia a pandillas, además resalta áreas donde las intervenciones pueden resultar prometedoras dentro de cada uno de los dominios: familiar, escolar y comunitario; por lo que proporciona un punto de partida para estudios futuros.

    ¿Cuán actualizada es esta revisión?

    Los revisores buscaron estudios publicados hasta septiembre de 2013. Esta revisión sistemática Campbell se publicó en diciembre de 2018.

Police-initiated diversion for youth to prevent future delinquent behavior
  • Authors David B. Wilson, Iain Brennan, Ajima Olaghere
  • Published date 2018-06-01
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Police-initiated diversion for youth to prevent future delinquent behavior
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.5
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Police-led diversion of low-risk youth reduces their future contact with the justice system

    Police-led diversion of low-risk youth who come into contact with the justice system is more effective in reducing a youth’s future contact with the justice system compared to traditional processing.

    What is this review about?

    Youth misconduct and misbehavior is a normal part of adolescence and that misbehavior sometimes crosses the line from disruptive or problematic to delinquent. Nationally representative surveys of youth in the USA have indicated that minor delinquent behavior is normative, particularly for boys. The normative nature of minor delinquent behavior raises the question of how police should respond to minor delinquent behavior in a way that is corrective, but also avoids involving the youth in the criminal justice system beyond what will be effective in reducing future misbehavior.

    Police diversion schemes are a collection of strategies police can apply as an alternative to court processing of youth. Diversion as an option is popular among law enforcement officers, as it provides an option between ignoring youth engaged in minor wrongdoing and formally charging such youth with a crime. Police-led diversion has the potential to reduce reoffending by limiting the exposure of low-risk youth to potentially harmful effects of engagement with the criminal justice system.

    This review examined whether police-led diversion and traditional processing of youth have different effects on rates of official delinquency.

    What is the aim of this review?

    This Campbell systematic review examines the effects police-initiated diversion programs on delinquent behavior, compared to traditional system processing. The review summarizes evidence from nineteen high-quality studies, including 13 randomized controlled trials and 6 quasi-experimental studies.

    What are the main findings of this review?

    This review includes studies that evaluated the effects of police-led diversionary practices compared to traditional processing for youth under 18 years of age. We identified a total of 14 manuscripts representing 19 evaluations. Of these 19 evaluations, 13 used randomized controlled designs (random assignment to conditions) and 6 used quasi-experimental designs (no random assignment to conditions). Many of these designs included two or more diversionary conditions compared to a common control (traditional processing) producing 31 treatment-comparison contrasts for analysis. These studies were conducted between 1973 and 2011, inclusively. Most were conducted in the USA (11) with the remaining conducted in Canada (4), Australia (2), and the UK (2).

    The general pattern of evidence is positive, suggesting that police-led diversion reduces the future delinquent behavior of low-risk youth relative to traditional processing. Assuming a 50 percent reoffending rate for the traditional processing condition, the results suggest a reoffending rate of roughly 44 percent for the diverted youth. This overall benefit of diversion holds for the random assignment studies judged to be free from any obvious risks of bias. No meaningful differences were found across types of diversionary programs. Furthermore, we found no evidence to suggest these findings suffer from publication selection bias.

    What do the findings of this review mean?

    The findings from this systematic review support the use of police-led diversion for low-risk youth with limited or no prior involvement with the juvenile justice system. Thus, police departments and policy-makers should consider diversionary programs as part of the mix of solutions for addressing youth crime.

    Many of the studies included in the review were conducted in the 1970s and 1980s. Newer high quality studies are needed to ensure that the findings still hold for contemporary juvenile justice contexts. Additional studies are also needed outside of the USA for this same reason. Finally, we recommend that research explore the usefulness of diversion for low-risk adult offenders.

    How up-to-date is this review?

    The authors searched for studies up to January 2017.

  • Spanish

    RESUMEN EN LENGUAJE SENCILLO

    La reorientación policial para jóvenes de bajo riesgo reduce sus posibilidades de ingresar en el sistema de penal más adelante

    La reorientación policial para jóvenes de bajo riesgo que se enfrentan al sistema penal es más efectiva en reducir futuros enfrentamientos con el sistema, a diferencia del procesamiento tradicional.

    ¿Cuál es el tema que trata esta revisión?

    La mala conducta es parte normal de la adolescencia, aunque a veces pasa de ser simplemente disruptiva o problemática a transformarse en algo netamente delictivo. Los sondeos a escala nacional acerca de los jóvenes en los EE.UU. indican que la conducta delictual leve es normal, especialmente en el caso de los varones. Esta normalidad del comportamiento delictivo leve plantea la cuestión de cómo la policía debe responder a ella para corregirla, pero que también evite involucrar a los jóvenes con el sistema penal más allá de lo que se considera efectivo para reducir la mala conducta en el futuro.

    Los programas de reorientación policial son un conjunto de estrategias que la policía puede implementar para los jóvenes como una alternativa al procesamiento judicial. La reorientación es bien recibida por los policías, ya que permite un camino alternativo entre el ignorar a los jóvenes involucrados en delitos leves y el acusarlos formalmente de cometer un delito. La reorientación policial tiene el potencial de reducir la reincidencia al limitar la exposición de los jóvenes de bajo riesgo a los efectos potencialmente dañinos de verse involucrados con el sistema penal.

    Esta revisión examinó si la reorientación policial y el procesamiento tradicional de los jóvenes tienen efectos distintos sobre las tasas de delincuencia oficial.

    ¿Cuál es el objetivo de esta revisión?

    Esta revisión sistemática Campbell examina los efectos de los programas de reorientación policial sobre el comportamiento delictivo en comparación con el sistema de procesamiento tradicional. La revisión resume la evidencia de diecinueve estudios de alta calidad, incluidos 13 ensayos controlados aleatorios y 6 estudios cuasiexperimentales.

    ¿Cuáles son los principales hallazgos de esta revisión?

    Esta revisión incluye estudios que evaluaron los efectos de las prácticas de reorientación policial en comparación con el procesamiento tradicional para jóvenes menores de 18 años. Se identificó un total de 14 documentos con 19 evaluaciones. De estas 19 evaluaciones, 13 utilizaron diseños controlados aleatorios (asignación aleatoria a las condiciones) y 6 utilizaron diseños cuasi-experimentales (sin asignación aleatoria a las condiciones). Muchos de estos diseños incluyeron dos o más condiciones de reorientación en comparación con un control común (procesamiento tradicional), produciendo 31 contrastes de comparación de tratamientos para el análisis. Estos estudios se realizaron entre 1973 y 2011, inclusivamente. La mayoría se realizaron en EE. UU. (11) y el resto se realizó en Canadá (4), Australia (2) y el Reino Unido (2).

    El patrón general de la evidencia es positivo, lo cual sugiere que la reorientación policial reduce el futuro comportamiento delictual de los jóvenes de bajo riesgo en comparación al procesamiento tradicional. Suponiendo una tasa de reincidencia del 50 por ciento para el procesamiento tradicional, los resultados sugieren una tasa de reincidencia de aproximadamente 44 por ciento para los jóvenes reorientados. Este beneficio general de la reorientación es válido para los estudios de asignación aleatoria considerados libres de cualquier riesgo evidente de sesgo. No se encontraron diferencias significativas entre los tipos de programas de reorientación. Asimismo, no encontramos evidencia que sugiera que estos hallazgos sufren de sesgos de selección de publicaciones.

    ¿Qué significan los hallazgos de esta revisión?

    Los hallazgos de esta revisión sistemática respaldan la utilización de la reorientación policial para jóvenes de bajo riesgo que hayan tenido pocos o nulos enfrentamientos con el sistema penal de menores. Por lo tanto, los departamentos de policía y los formuladores de políticas deben considerar los programas de reorientación como parte de las soluciones utilizadas para abordar la delincuencia juvenil.

    Varios de los estudios incluidos en la revisión se llevaron a cabo en los años 70 y 80. Se requieren estudios de alta calidad más recientes para garantizar que los hallazgos se mantengan vigentes en contextos de justicia juvenil actuales. También, y por esta misma razón, se requieren estudios adicionales fuera de EE.UU. Finalmente, se recomienda que futuras investigaciones exploren la utilidad de la reorientación para los delincuentes adultos de bajo riesgo.

    ¿Qué tan actualizada es esta revisión?

    Nuestra búsqueda de estudios elegibles se completó en enero de 2017, por lo que solo se incluyeron estudios identificables hasta enero de 2017. Esta revisión sistemática Campbell se publicó en mayo de 2018.

School-based interventions for reducing disciplinary school exclusion
  • Authors Sara Valdebenito, Manuel Eisner, David P. Farrington, Maria M. Ttofi, Alex Sutherland
  • Published date 2018-01-09
  • Coordinating group(s) Crime and Justice, Education
  • Type of document Review Plain language summary
  • Title School-based interventions for reducing disciplinary school exclusion
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.1
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Interventions can reduce school exclusion but the effect is temporary

    Interventions to reduce school exclusion are intended to mitigate the adverse effects of this school sanction.
Some approaches, namely those involving enhancement of academic skills, counselling, mentoring/monitoring and those targeting skills training for teachers, have a temporary effect in reducing exclusion. More evaluations are needed to identify the most effective types of intervention; and whether similar effects are also found in different countries.

    What did the review study?

    School exclusion is associated with undesirable effects on developmental outcomes. It increases the likelihood
of poor academic performance, antisocial behavior, and poor employment prospects. This school sanction disproportionally affects males, ethnic minorities, those who come from disadvantaged economic backgrounds, and those with special educational needs.

    This review assesses the effectiveness of programmes to reduce the prevalence of exclusion.

    What is the aim of this review?

    This Campbell systematic review examines the impact of interventions to reduce exclusion from school. School exclusion, also known as suspension in some countries, is a disciplinary sanction imposed by a responsible school authority, in reaction to students’ misbehaviour. Exclusion entails the removal of pupils from regular teaching for a period during which they are not allowed to be present in the classroom (in-school) or on school premises (out-of-school). In some extreme cases the student is not allowed to come back to the same school (expulsion). The review summarises findings from 37 reports covering nine different types of intervention. Most studies were from the USA, and the remainder from the UK.

    What studies are included?

    Included studies evaluated school-based interventions or school-supported interventions to reduce the rates of exclusion. Interventions were implemented in mainstream schools and targeted school-aged children from four to 18, irrespective of nationality or social background. Only randomised controlled trials are included.

    The evidence base covers 37 studies. Thirty-three studies were from the USA, three from the UK, and for one study the country was not clear.

    What are the main results in this review?

    School-based interventions cause a small and significant drop in exclusion rates during the first six months after intervention (on average), but this effect is not sustained. Interventions seemed to be more effective at reducing some types of exclusion such as expulsion and in-school exclusion.

    Four intervention types - enhancement of academic skills, counselling, mentoring/ monitoring, and skills training for teachers – had significant desirable effects on exclusion. However, the number of studies in each case is low, so this result needs to be treated with caution.

    There is no impact of the interventions on antisocial behaviour.

    Variations in effect sizes are not explained by participants’ characteristics, the theoretical basis of the interventions, or the quality of the intervention. Independent evaluator teams reported lower effect sizes than research teams who were also involved in the design and/or delivery of the intervention.

    What do the findings in this review mean?

    School-based interventions are effective at reducing school exclusion immediately after,
and for a few months after, the intervention (6 months on average). Four interventions presented promising and significant results in reducing exclusion, that is, enhancement of academic skills, counselling, mentoring/monitoring, skills training for teachers. However, since the number of studies for each sub-type of intervention was low, we suggest these results should be treated with caution.

    Most of the studies come from the USA. Evaluations are needed from other countries in which exclusion is common. Further research should take advantage of the possibility of conducting cluster-randomised controlled trials, whilst ensuring that the sample size is sufficiently large.

    How up-to-date is this review?

    The review authors searched for studies published up to December 2015.

  • Spanish

    RESUMEN EN LENGUAJE SENCILLO

    Algunas intervenciones para reducir la exclusión escolar funcionan, pero su efecto es temporal

    Las intervenciones que reducen la exclusión intentan mitigar los efectos adversos de esta sanción. Las intervenciones destinadas a mejorar las habilidades académicas de los estudiantes, la consejería, los programas de apoyo personalizado a los estudiantes (mentores/monitores) y aquellos que se enfocan en mejorar las habilidades de manejo conductual de los profesores, tienen un efecto positivo temporal. Es necesario desarrollar más evaluaciones para identificar la intervención más efectiva; y también para testear si estos efectos son similares en otros países.

    ¿De qué trata esta revisión sistemática?

    La exclusión escolar se asocia con efectos no deseados en el desarrollo de los niños. Estudios previos muestran una asociación consistente entre la exclusión y el bajo rendimiento académico, conducta antisocial y dificultades de inserción en el mercado laboral. Esta sanción afecta de manera desproporcionada a los varones, a las minorías étnicas, a aquellos que provienen de ambientes socioeconómicos deprivados y también a los estudiantes con necesidades educativas especiales.

    Esta revisión sistemática analiza la efectividad de los programas de intervención para reducir la prevalencia de la exclusión escolar.

    ¿Cuál es el objetivo de esta revisión sistemática?

    Esta revisión sistemática de Campbell examina el impacto de algunas intervenciones en la reducción de la exclusión escolar. La exclusión, también conocida como “suspensión” en algunos países, es una sanción impuesta por la autoridad escolar, en reacción a los problemas de disciplina de un estudiante. Los estudiantes excluidos no están autorizados para participar de las actividades académicas en la sala de clases (exclusión en la escuela) o, en otros casos, no están autorizados para estar presentes en la escuela (exclusión de la escuela). En casos extremos, la sanción prohíbe al estudiante retornar a su escuela de manera definitiva y éste debe ser reubicado en otra institución (expulsión).

    Esta revisión sistemática reporta los resultados de 37 estudios que incluyen nueve tipos diferentes de intervenciones. La mayoría de los estudios fueron realizados en los Estados Unidos y el resto se condujo en el Reino Unido.

    ¿Qué estudios se incluyen?

    Los estudios incluidos en esta revisión evalúan el impacto de las intervenciones en la reducción de la exclusión. Las intervenciones incluidas fueron implementadas en escuelas regulares e incluyeron a estudiantes de entre 4 y 18 años. Todos los estudios incluidos corresponden a ensayos controlados aleatorios.

    El meta-análisis incluye 37 estudios: 33 ejecutados en los Estados Unidos, tres en el Reino Unido y uno en cuyo caso no fue posible determinar el país de origen de la muestra.

    ¿Cuáles son los principales resultados de esta revisión sistemática?

    Las intervenciones estudiadas provocan una pequeña, aunque significativa reducción de la exclusión durante los primeros seis meses (en promedio), pero su efecto tiende a diluirse en el largo plazo. Los resultados más promisorios se observaron en la reducción de la exclusión que se ejecuta dentro de la escuela y para el caso de las expulsiones. Cuatro tipos de intervenciones (mejorar habilidades académicas, consejería, mentores/monitores y entrenamiento de habilidades de los profesores) demostraron ser las más efectivas. Debido a que el número de estudios en cada sub-grupo es limitado, los resultados de este estudio deben ser analizados con cautela.

    Las intervenciones estudiadas mostraron no tener impacto en la conducta antisocial. Las variaciones en los efectos incluidos, no se explicaron por las características de los participantes, las bases teóricas de las intervenciones o la calidad de éstas. Los evaluadores independientes reportaron efectos más bajos que aquellos investigadores que además de evaluar habían tomado parte en el diseño y la ejecución de las intervenciones.

    ¿Qué significan los resultados de esta revisión sistemática?

    Las intervenciones estudiadas tienen un efecto significativo en la reducción de la exclusión en el periodo inmediatamente posterior a las intervenciones y por los meses subsiguientes (seis meses en promedio). Cuatro intervenciones presentaron resultados promisorios: mejoramiento de las habilidades académicas, la consejería, los programas de mentores/ monitores y aquellos que se enfocan en mejorar las habilidades de los profesores. Sin embargo, dado el bajo número de estudios incluidos en el análisis de subgrupos, se recomienda interpretar estos resultados con cautela.

    La mayoría de los estudios incluidos en esta revisión fueron ejecutados en los Estados Unidos. Es importante contar con evaluaciones en otros países. Se sugiere que estudios futuros exploren la posibilidad de realizar ensayos controlados aleatorios en clusters y asegurar al mismo tiempo el uso de muestras robustas con suficiente poder estadístico.

    ¿Qué tan actualizada es esta revisión?

    Los autores realizaron búsquedas de estudios hasta diciembre de 2015. Esta revisión ha sido publicada en enero de 2018.

Sexual offender treatment for reducing recidivism among convicted sex offenders
  • Authors Martin Schmucker, Friedrich Loesel
  • Published date 2017-07-31
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Sexual offender treatment for reducing recidivism among convicted sex offenders
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2017.8
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Treatment of sexual offenders reduces reoffending, but more research needed to identify effective interventions

    Treatment can reduce reoffending (recidivism) rates of sexual offenders. But the results of individual studies are too heterogeneous to draw a conclusion on the general effectiveness of sex offender treatment.

    What is this review about?

    Sexual offender treatment programs to reduce reoffending have been implemented in many countries as part of a strategy in managing this offender group. However, there are still controversies regarding their effectiveness.

    This review integrates findings from six experimental and 21 quasi-experimental studies that compare groups of treated sexual offenders with equivalent control groups. These studies tested whether treated sexual offenders differed from the control groups in sexual and other reoffending.

    What is the aim of this review?

    This Campbell systematic review examines the effectiveness of treatment for sexual offenders to reduce reoffending and the factors that affect treatment success. The review summarises evidence from 27 impact evaluations.

    What studies are included?

    Included studies compare official recidivism rates of treated sexual offenders with a comparable group of sexual offenders that have not been subjected to the respective treatment. Quasi-experimental studies were included only if they applied sound matching procedures, where the incidental assignment would not introduce bias, or where they were statistically controlled for potential biases. The treatment had to explicitly aim at reducing recidivism rates.

    The review summarizes 27 studies containing 29 eligible comparisons of a treated group and a control group, containing data for 4,939 treated and 5,448 untreated sexual offenders. The studies come from seven different countries, but more than half of the studies have been carried out in North America. All eligible comparisons evaluated psychosocial treatment (mainly cognitive behavioral programs). No studies on pharmacological/hormonal treatment were found which meet the inclusion criteria.

    What are the main findings of this review?

    Does treatment of sexual offenders reduce recidivism?

    On average, there is a significant reduction in recidivism rates in the treated groups. The odds to sexually reoffend were 1.41 lower for treated compared to control groups. This equals a sexual recidivism rate of 10.1 percent for treated offenders compared to 13.7 percent without treatment. The mean rates for general recidivism were higher, but showed a similar reduction of roughly a quarter due to treatment.

    The results from the individual studies were very heterogeneous, that is individual study features had a strong impact on the outcomes. Methodological quality did not significantly influence effect sizes. Cognitive-behavioral as well as studies with small samples, medium to high risk offenders, more individualized treatment, and good descriptive validity revealed better effects. There was no significant difference between various settings. We found significant effects for treatment in the community and in forensic hospitals, but there is not yet sufficient evidence to draw conclusions regarding the effectiveness of sex offender treatment in prisons.

    What do the findings in this review mean?

    Overall, the findings are promising, but there is too much heterogeneity between the results of individual studies to draw a generally positive conclusion about the effectiveness of sex offender treatment. Applied cognitive-behavioral foundation of treatment has relatively good potential, but other features, like the risk of the treated offenders or including individualized treatment, significantly affect treatment success.

    More well documented randomized trials and high-quality quasi-experiments are needed, particularly outside of North America. In addition, there is a clear need of more differentiated process and outcome evaluations.

    How up-to-date is this review?

    The study pool of the present analysis was based on the broad search of 2,039 documents from a review published in 2005, updated to cover studies issued prior to 2010. More recent studies were evaluated in an appendix and mostly showed similar findings as in our review.

  • Spanish

    RESUMEN EN LENGUAJE SENCILLO

    El tratamiento de los delincuentes sexuales reduce la reincidencia, aunque se necesita más investigación para identificar cuáles intervenciones son efectivas

    El tratamiento puede reducir las tasas de reincidencia (recaída) de delincuentes sexuales. Sin embargo, los resultados de los estudios individuales son demasiado heterogéneos como para poder sacar conclusiones acerca de la efectividad general del tratamiento de delincuentes sexuales.

    ¿Cuál es el tema que trata esta revisión?

    En muchos países se han implementado programas de tratamiento de delincuentes sexuales para reducir la reincidencia, como parte de una estrategia de manejo de este grupo de delincuentes. No obstante, existe controversia con respecto a su efectividad.

    Esta revisión integra los hallazgos de seis estudios experimentales y 21 estudios cuasi experimentales, los cuales comparan grupos de delincuentes sexuales tratados, con grupos de control equivalentes. Estos estudios probaron si los delincuentes sexuales tratados diferían del grupo de control en la reincidencia de delitos sexuales y de otro tipo.

    ¿Cuál es el objetivo de esta revisión?

    Esta Revisión Sistemática Campbell examina la efectividad del tratamiento de delincuentes sexuales para reducir la reincidencia y los factores que afectan el éxito del tratamiento. La revisión resume la evidencia de 27 evaluaciones de impacto.

    ¿Cuáles son los principales hallazgos de esta revisión?

    ¿Qué estudios se incluyen?

    Los estudios incluidos comparan las tasas oficiales de reincidencia de los delincuentes sexuales tratados, con un grupo comparable de delincuentes sexuales que no han sido sometidos al tratamiento respectivo. Solo se incluyeron estudios cuasi experimentales que aplicaban procedimientos fiables, en los que la asignación al tratamiento no introducía sesgos, o aquellos que eran controlados estadísticamente frente a posibles sesgos. El tratamiento debía tener como objetivo explícito la reducción de las tasas de reincidencia.

    La revisión resume 27 estudios que contienen 29 comparaciones elegibles de un grupo de tratamiento y un grupo control, incluyendo datos para 4.939 delincuentes sexuales tratados y 5.448 no tratados. Los estudios provienen de siete países, sin embargo, más de la mitad de ellos se han realizado en Norteamérica. Todas las comparaciones elegibles evaluaron el tratamiento psicosocial (principalmente programas cognitivoconductuales). No se encontraron estudios sobre el tratamiento farmacológico-hormonal que cumplieran con los criterios de inclusión.

    ¿El tratamiento de los delincuentes sexuales reduce la reincidencia?

    Existe en promedio una reducción significativa en las tasas de reincidencia para los grupos tratados. Las probabilidades de reincidir en delitos sexuales fueron 1,41 menores para los grupos tratados, en comparación con los grupos de control. Esto equivale a una tasa de reincidencia de delitos sexuales del 10,1 por ciento para los delincuentes tratados, en comparación con el 13,7 por ciento para el grupo sin tratamiento. Las tasas medias para la reincidencia general fueron más altas, aunque mostraron una reducción similar de aproximadamente una cuarta parte debido al tratamiento.

    Los resultados de los estudios individuales fueron muy heterogéneos, es decir, las características del estudio individual tuvieron un fuerte impacto en los resultados. La calidad metodológica no influyó significativamente en el tamaño del efecto. Los estudios cognitivo-conductuales, así como aquellos estudios con muestras pequeñas, delincuentes de riesgo medio a alto, tratamientos más individualizados y una buena validez descriptiva, revelaron mejores efectos. No hubo una diferencia significativa entre los diversos escenarios. Encontramos efectos significativos para el tratamiento en la comunidad y en los hospitales forenses; sin embargo, aún no existe evidencia suficiente que permita sacar conclusiones con respecto a la efectividad del tratamiento de delincuentes sexuales en las cárceles.

    ¿Qué significan los resultados de esta revisión?

    En general, los hallazgos son prometedores; sin embargo, existe demasiada heterogeneidad entre los resultados de los estudios individuales como para sacar una conclusión positiva en conjunto sobre la efectividad del tratamiento de los delincuentes sexuales. La base cognitiva-conductual aplicada del tratamiento tiene un potencial relativamente bueno; no obstante, existen otras características, tales como el riesgo de los delincuentes tratados o la inclusión de tratamiento individualizado, que afectan significativamente el éxito del tratamiento.

    Se necesitan más ensayos controlados aleatorios bien documentados y cuasi experimentos de alta calidad, especialmente fuera de Norteamérica. Además, existe una clara necesidad de contar con más procesos diferenciados y evaluaciones de resultados.

    ¿Cuán actualizada es esta revisión?

    El grupo de estudios del presente análisis se basó en la búsqueda general de 2.039 documentos de una revisión publicada en 2005, actualizada para abarcar los estudios publicados antes de 2010. Los estudios más recientes se evaluaron en un apéndice, mostrando en su mayoría resultados similares a los de nuestra revisión. Esta Revisión Sistemática Campbell fue publicada en julio de 2017.

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