Better evidence for a better world

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Better evidence for a better world
Better evidence for a better world

Better evidence for a better world (173)

Additional Info

  • Authors Brandy R. Maynard, Anne Farina, Nathaniel A. Dell, Michael S. Kelly
  • Published date 2019-07-17
  • Coordinating group(s) Education
  • Type of document Review
  • Title Effects of trauma-informed approaches in schools
  • See the full review https://onlinelibrary.wiley.com/doi/10.1002/cl2.1018
  • English

    PLAIN LANGUAGE SUMMARY

    The review in brief

    Despite growing support and increased rate of which trauma‐informed approaches are being promoted and implemented in schools, evidence to support this approach is lacking.

    What is this review about?

    Exposure to different types of trauma have been associated with varying types and complexity of adverse outcomes, including adverse effects on cognitive functioning, attention, memory, academic performance, and school‐related behaviors. Given the growing research on trauma and increased knowledge about the prevalence, consequences and costs associated with trauma, there have been increased efforts at the local, state and federal levels to make systems “trauma‐informed” (Lang, Campbell, & Vanerploeg, 2015). While the intent of creating trauma‐informed approaches in schools is a noble one, relatively little is known about the benefits, costs, and how trauma‐informed approaches are being defined and evaluated (Berliner & Kolko, 2016). Adopting a trauma‐informed approach in a complex system such as a school building or district is a time consuming and potentially costly endeavor and thus it is important to assess the effects of this approach to inform policy and practice.

    This aim of this review was to assess trauma‐informed approaches in schools on trauma symptoms/mental health, academic performance, behavior, and socioemotional functioning. Trauma‐informed approaches include programs, organizations, or systems that realize the impact of trauma, recognize the symptoms of trauma, respond by integrating knowledge about trauma policies and practices, and seeks to reduce retraumatization. At least two of the three key elements of a trauma‐informed approach must have been present: Workforce development, trauma‐focused services, and organizational environment and practices, which differ from trauma‐specific interventions designed to treat or otherwise address the impact/symptoms of trauma and facilitate healing.

    What is the aim of this review?

    This Campbell systematic review sought to examine the effects trauma‐informed schools on trauma symptoms/mental health, academic performance, behavior, and socioemotional functioning. Although we conducted a comprehensive search to find studies testing trauma‐informed approaches in schools, no studies met the inclusion criteria.

    What are the main findings of this review?

    No studies met criteria for this review, indicating that there is a lack of evidence of trauma‐informed approaches in schools.

    What do the findings of this review mean?

    Despite widespread support and growing adoption of trauma‐informed approaches in schools across the globe, we found no studies to provide good evidence to suggest that this approach is effective in achieving the stated goals. Given the degree to which trauma‐informed approaches are being adopted in schools across the US and other countries, it is important that the effects of these programs be assessed.

    How up‐to‐date is this review?

    The review authors searched for studies June through September, 2017.

Additional Info

  • Published date 2019-06-01
  • Title Other evidence and gap maps (EGMs)

Additional Info

  • Authors Padraic Fleming, Sinead McGilloway, Marian Hernon, Mairead Furlong, Siobhain O’Doherty, Fiona Keogh, Tim Stainton
  • Published date 2019-01-25
  • Coordinating group(s) Disability
  • Type of document Review Plain language summary
  • Title Individualized funding interventions to improve health and social care outcomes for people with a disability
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2019.3
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Individualised funding has positive effects on health and social care outcomes

    Individualised funding provides personal budgets for people with disabilities, to increase independence and quality of life. The approach has consistently positive effects on overall satisfaction, with some evidence also of improvements in quality of life and sense of security. There may also be fewer adverse effects. Despite implementation challenges, recipients generally prefer this intervention to traditional supports.

    What is this review about?

    Individualised funding is an umbrella term for disability supports funded on an individual basis. It aims to facilitate self-direction, empowerment, independence and self-determination. This review examines the effects and experiences of individualised funding.

    What is the aim of this review?

    This Campbell systematic review examines the effects of individualised funding on a range of health and social care outcomes. It also presents evidence on the experiences of people with a disability, their paid and unpaid supports and implementation successes and challenges from the perspective of both funding and support organisations.

    What are the main findings of this review?

    This study is a review of 73 studies of individualised funding for people with disabilities. These include four quantitative studies, 66 qualitative and three based on a mixed-methods design. The data refer to a 24-year period from 1992 to 2016, with data for 14,000 people. Studies were carried out in Europe, the US, Canada and Australia.

    What studies are included?

    Overall, the evidence suggests positive effects of individualised funding with respect to quality of life, client satisfaction and safety. There may also be fewer adverse effects. There is less evidence of impact for physical functioning, unmet need and cost effectiveness. The review finds no differences between approaches for the Adult Social Care Outcomes Toolkit (ASCOT), self-perceived health and community participation.

    Recipients particularly value: flexibility, improved self-image and self-belief; more value for money; community integration; freedom to choose ‘who supports you; ‘social opportunities’; and needs-led support. Many people chose individualised funding due to previous negative experiences of traditional, segregated, group-orientated supports.

    Successful implementation is supported by strong, trusting and collaborative relationships in their support network with both paid and unpaid individuals. This facilitates processes such as information sourcing, staff recruitment, network building and support with administrative and management tasks. These relationships are strengthened by financial recognition for family and friends, appropriate rates of pay, a shift in power from agencies to the individual or avoidance of paternalistic behaviour.

    Challenges include long delays in accessing and receiving funds, which are compounded by overly complex and bureaucratic processes. There can be a general lack of clarity (e.g. allowable budget use) and inconsistent approaches to delivery as well as unmet information needs. Hidden costs or administrative charges can be a source of considerable concern and stress.

    Staff mention involvement of local support organisations, availability of a support network for the person with a disability and timely relevant training as factors supporting implementation. Staff also highlight logistical challenges in support needs in an individualised way including, for example, responding to individual expectations, and socio-demographic differences.

    What do the findings of this review mean?

    This review provides an up-to-date and in-depth synthesis of the available evidence over 25 years. It shows that there are benefits of the individualised funding model. This finding suggests that practitioners and funders should consider moving away from scepticism, towards opportunity and enthusiasm. Policy makers need to be aware of the set-up and transitionary costs involved. Investment in education and training will facilitate deeper understanding of individualised funding and the mechanisms for successful implementation.

    Future studies should incorporate longer follow-ups at multiple points over a longer period. The authors of the review encourage mixed-methods approaches in further systematic reviews in the field of health and social care, to provide a more holistic assessment of the effectiveness and impact of complex ‘real-world’ interventions.

    How up-to-date is this review?

    The review authors searched for studies up to the end of 2016. This Campbell systematic review was published in January 2019.

  • Spanish

    Click on 'Download PDF' on the right to view the plain language summary in Spanish.

Additional Info

  • Authors Maren Duvendack, Philip Mader
  • Published date 2019-01-07
  • Coordinating group(s) International Development, Methods
  • Type of document Review Plain language summary
  • Title Impact of financial inclusion in low‐ and middle‐income countries: A systematic review of reviews
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2019.2
  • Records available in English, Hindi, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Financial inclusion interventions have very small and inconsistent impacts

    A wide range of financial inclusion programmes seek to increase poor people’s access to financial services to enhance the welfare of poor and low-income households in low- and middle-income countries. The impacts of financial inclusion interventions are small and variable. Although some services have some positive effects for some people, overall financial inclusion may be no better than comparable alternatives, such as graduation or livelihoods interventions.

    What is this review about?

    Financial inclusion programmes seek to increase access to financial services such as credit, savings, insurance and money transfers and so allow poor and low-income households in low- and middle-income countries to enhance their welfare, grasp opportunities, mitigate shocks, and ultimately escape poverty.  This systematic review of reviews assesses the evidence on economic, social, behavioural and gender-related outcomes from financial inclusion.

    What is the aim of this review?

    This systematic review of reviews systematically collects and appraises all of the existing meta-studies – that is systematic reviews and meta-analyses – of the impact of financial inclusion. The authors first analyse the strength of the methods used in those meta-studies, then synthesise the findings from those that are of a sufficient quality, and finally, report the implications for policy, programming, practice and further research arising from the evidence. Eleven studies are included in the analysis.

    What are the main findings of this review?

    What studies are included?

    This review includes studies that synthesise the findings of other studies (meta-studies) regarding the impacts of a range of financial inclusion interventions on economic, social, gender and behavioural outcomes. A total of 32 such meta-studies were identified, of which 11 were of sufficient methodological quality to be included in the final analysis. The review examined meta-studies from 2010 onwards that spanned the globe in terms of geographical coverage.

    Impacts are more likely to be positive than negative, but the effects vary, are often mixed, and appear not to be transformative in scope or scale, as they largely occur in the early stages of the causal chain of effects. Overall, the effects of financial services on core economic poverty indicators such as incomes, assets or spending, and on health status and other social outcomes, are small and inconsistent. Moreover, there is no evidence for meaningful behaviour-change outcomes leading to further positive effects.

    The effects of financial services on women’s empowerment appear to be generally positive, but they depend upon programme features which are often only peripheral or unrelated to the financial service itself (such as education about rights), cultural and geographical context, and what aspects of empowerment are considered.

    Accessing savings opportunities appears to have small but much more consistently positive effects for poor people, and bears fewer downside risks for clients than credit. A large number of the meta-studies included in the final analysis voiced concerns about the low quality of the primary evidence base that formed the basis of their syntheses. This raises concerns about the reliability of the overall findings of meta-studies.

    What do the findings of this review mean?

    This systematic review of reviews draws on the largest-ever evidence base on financial inclusion impacts.  The weak effects found warn against unrealistic hype for financial inclusion, as previously happened for microcredit. There are substantial evidence gaps, notably studies of sufficient duration to measure higher-level impacts which take time to materialize, and for specific outcomes such as debt levels or indebtedness patterns and the link to macroeconomic development.

    This study is the first review of reviews published by the Campbell Collaboration. Some important limitations were encountered working at this level of systematisation.  It is recommended that authors of primary studies and meta-studies engage more critically with study quality and ensure better, more detailed reporting of their concepts, data and methods. More methods guidance and clearer reporting standards for the social science and international development context would be helpful.

    How up-to-date is this review?

    The review authors searched for studies in November 2017, updating elements of the searches in January 2018. This Campbell Systematic Review was published in January 2019.

  • Spanish

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  • Hindi

    Click on 'Download PDF' on the right to view the plain language summary in Hindi.

Additional Info

  • 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.

Additional Info

  • 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

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Additional Info

  • Authors Trine Filges, Christoffer Scavenius Sonne-Schmidt, Bjørn Christian Viinholt Nielsen
  • Published date 2018-10-11
  • Coordinating group(s) Education
  • Type of document Review Plain language summary
  • Title Small class sizes for improving student achievement in primary and secondary schools
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.10
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Small class size has at best a small effect on academic achievement, and may harm some students

    Reducing class size is seen as a way of improving student performance. But larger class sizes help control education budgets. The evidence suggests at best a small effect on reading achievement. There is a negative, but statistically insignificant, effect on mathematics, so it cannot be ruled out that some children may be adversely affected.

    What is this review about?

    Increasing class size is one of the key variables that policy makers can use to control spending on education.

    But the consensus among many in education research is that smaller classes are effective in improving student achievement which has led to a policy of class size reductions in a number of U.S. states, the United Kingdom, and the Netherlands. This policy is disputed by those who argue that the effects of class size reduction are only modest and that there are other more cost-effective strategies for improving educational standards.

    Despite the important policy and practice implications of the topic, the research literature on the educational effects of class-size differences has not been clear.

    This review systematically reports findings from relevant studies that measure the effects of class size on academic achievement.

    What is the aim of this review?

    This Campbell systematic review examines the impact of class size on academic achievement. The review summarises findings from 148 reports from 41 countries. Ten studies were included in the meta-analysis.

    What studies are included?

    Included studies concerned children in grades kindergarten to 12 (or the equivalent in European countries) in general education. The primary focus was on measures of academic achievement. All study designs that used a well-defined control group were eligible for inclusion.

    A total of 127 studies, consisting of 148 papers, met the inclusion criteria. These 127 studies analysed 55 different populations from 41 different countries. A large number of studies (45) analysed data from the Student Teacher Achievement Ratio (STAR) experiment which was for class size reduction in grade K-3 in the US in the eighties. However only ten studies, including four of the STAR programme, could be included in the meta-analysis.

    What are the main results in this review?

    Overall, the evidence suggests at best a small effect on reading achievement. There is a negative, but statistically insignificant, effect on mathematics.

    For the non-STAR studies the primary study effect sizes for reading were close to zero but the weighted average was positive and statistically significant. There was some inconsistency in the direction of the primary study effect sizes for mathematics and the weighted average effect was negative and statistically non-significant.

    The STAR results are more positive, but do not change the overall finding. All reported results from the studies analysing STAR data indicated a positive effect of smaller class sizes for both reading and maths, but the average effects are small.

    What do the findings in this review mean?

    There is some evidence to suggest that there is an effect of reducing class size on reading achievement, although the effect is very small. There is no significant effect on mathematics achievement, though the average is negative meaning a possible adverse impact on some students cannot be ruled out.

    The overall reading effect corresponds to a 53 per cent chance that a randomly selected score of a student from the treated population of small classes is greater than the score of a randomly selected student from the comparison population of larger classes. This is a very small effect.

    Class size reduction is costly. The available evidence points to no or only very small effect sizes of small classes in comparison to larger classes. Moreover, we cannot rule out the possibility that small classes may be counterproductive for some students. It is therefore crucial to know more about the relationship between class size and achievement in order to determine where money is best allocated.

    How up-to-date is this review?

    The review authors searched for studies published up to February 2017.

  • Spanish

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Additional Info

  • Authors Emily A. Hennessy, Emily E. Tanner-Smith, Andrew J. Finch, Nila Sathe, Shannon Kugley
  • Published date 2018-10-04
  • Coordinating group(s) Education, Social Welfare
  • Type of document Review Plain language summary
  • Title Recovery schools for improving behavioral and academic outcomes among students in recovery from substance use disorders
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.9
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    There is insufficient evidence to know whether recovery high schools and collegiate recovery communities are effective

    Very limited evidence addresses the effectiveness of recovery high schools (RHSs). There is no rigorous evidence on the effectiveness of collegiate recovery communities (CRCs).

    What is this review about?

    Based on the results of one study, RHSs may reduce high school students’ school absenteeism, marijuana use, and other drug use, and increase abstinence from drugs; but RHSs may be no better or worse than other high schools in improving grades, reducing truancy, or reducing alcohol use.

    It is unclear whether CRCs are effective in promoting academic success and reducing substance use among college students.

    What is the aim of this review?

    This Campbell systematic review examines the effects of recovery schools on student behavioral and academic outcomes, compared to the effects of non-recovery schools. The review summarizes evidence from one quasi-experimental study (with a total of 194 participants) that had potential serious risk of bias due to confounding.

    What are the main findings of this review?

    Sizable portions of youth are in recovery from substance use disorders, and many youth will return to use after receiving substance use treatment. Youth spend most of their waking hours at school, and thus schools are important social environments for youth in recovery from substance use disorders. Recovery schools have been identified as educational programs that may help support youth in recovery from substance use disorders.

    This review focused on two types of recovery schools: RHSs, which are schools that award secondary school diplomas and offer a range of therapeutic services in addition to standard educational curricula; and CRCs, which offer therapeutic and sober support services on college campuses.

    This review looked at whether recovery schools (RHSs or CRCs) affect academic success and substance use outcomes among students, compared to similar students who are not enrolled in recovery schools.

    What studies are included?

    The included study of recovery high schools used a controlled quasi-experimental pretest-posttest design and reported on the following outcomes: grade point average, truancy, school absenteeism, alcohol use, marijuana use, other drug use, and abstinence from alcohol/drugs. The included study focused on a sample of U.S. high school students. There were no eligible studies of CRCs.

    What do the findings of this review tell us?

    Findings from this review indicate insufficient evidence on the effects of recovery schools on student well-being. Although there is some indication RHSs may improve academic and substance use outcomes, this is based on the findings from a single study. There is no available evidence on the effects of CRCs.

    No strong conclusions can be drawn at this time, given the lack of available evidence on RHSs and CRCs, and the serious risk of bias in the one RHS study included in the review. The evidence from this review suggests there is a clear need for additional rigorous evaluations of recovery school effects prior to widespread implementation.

    How up-to-date is this review?

    The review authors searched for studies until September 2018.

  • Spanish

    Click on 'Download PDF' on the right to view the plain language summary in Spanish.

Additional Info

  • Authors Jennifer Petkovic, Vivian Welch, Marie Helena Jacob, Manosila Yoganathan, Ana Patricia Ayala, Heather Cunningham, Peter Tugwell
  • Published date 2018-09-10
  • Coordinating group(s) Knowledge Translation and Implementation
  • Type of document Review Plain language summary
  • Title Do evidence summaries increase health policy-makers’ use of evidence from systematic reviews?
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2018.8
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Policy briefs make systematic reviews easier to understand but little evidence of impact on use of study findings

    It is likely that evidence summaries are easier to understand than complete systematic reviews. Whether these summaries increase the use of evidence from systematic reviews in policymaking is not clear.

    What is this review about?

    Systematic reviews are long and technical documents that may be hard for policymakers to use when making decisions. Evidence summaries are short documents that describe research findings in systematic reviews. These summaries may simplify the use of systematic reviews.

    Other names for evidence reviews are policy briefs, evidence briefs, summaries of findings, or plain language summaries. The goal of this review was to learn whether evidence summaries help policymakers use evidence from systematic reviews. This review also aimed to identify the best ways to present the evidence summary to increase the use of evidence.

    What is the aim of this review?

    This review summarizes the evidence from six randomized controlled trials that judged the effectiveness of systematic review summaries on policymakers’ decision making, or the most effective ways to present evidence summaries to increase policymakers’ use of the evidence.

    What are the main findings of this review?

    This review included six randomized controlled studies. A randomized controlled study is one in which the participants are divided randomly (by chance) into separate groups to compare different treatments or other interventions. This method of dividing people into groups means that the groups will be similar and that the effects of the treatments they receive will be compared more fairly. At the time the study is done, it is not known which treatment is the better one.

    The researchers who did these studies invited people from Europe, North America, South America, Africa, and Asia to take part in them. Two studies looked at “policy briefs,” one study looked at an “evidence summary,” two looked at a “summary of findings table,” and one compared a “summary of findings table” to an evidence summary.

    None of these studies looked at how policymakers directly used evidence from systematic reviews in their decision making, but two studies found that there was little to no difference in how they used the summaries. The studies relied on reports from decision makers. These studies included questions such as, “Is this summary easy to understand?”

    Some of the studies looked at users’ knowledge, understanding, beliefs, or how credible (trustworthy) they believed the summaries to be. There was little to no difference in the studies that looked at these outcomes. Study participants rated the graded entry format higher for usability than the full systematic review. The graded entry format allows the reader to select how much information they want to read. The study participants felt that all evidence summary formats were easier to understand than full systematic reviews.

    What do the findings of this review mean?

    Our review suggests that evidence summaries help policymakers better understand the findings presented in systematic reviews. In short, evidence summaries should be developed to make it easier for policymakers to understand the evidence presented in systematic reviews. However, right now there is very little evidence on the best way to present systematic review evidence to policymakers.

    How up-to-date is this review?

    The authors of this review searched for studies through June 2016.

  • Spanish

    Click on 'Download PDF' on the right to view the plain language summary in Spanish.

Additional Info

  • Authors Ruth Pitt
  • Published date 2018-08-22
  • Coordinating group(s) Crime and Justice
  • Type of document Policy brief
  • Title Policy brief 5: Effectiveness of focused policing strategies
  • Library Image Library Image
  • English

    This Campbell policy brief summarises findings from systematic reviews on focused policing strategies, the consequences of geographically-focused policing for neighbouring areas, and community perceptions of police legitimacy.

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