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 Jane Barlow
  • Published date 2016-06-20
  • Type of document Policy brief
  • Title Policy brief 1: Effects of parenting programmes
  • Library Image Library Image
  • Records available in English, Spanish
  • English

    Parenting programmes are provided to parents to enhance their knowledge, skills and understanding, and so improve both child and parent behavioural and psychological outcomes.

    These programmes are typically offered over eight to 12 weeks, for about one to two hours each week, although the range varies from as few as two sessions to as many as 20.

    Professor Barlow summarises evidence from six Campbell systematic reviews.

  • Spanish

    Efectos de programas de capacitación para padres: Una revisión de seis revisiones sistemáticas Campbell.

Additional Info

  • Authors Gary Ritter
  • Published date 2016-06-20
  • Type of document Policy brief
  • Title Policy brief 2: Effects of school-based interventions to improve student behavior
  • Library Image Library Image
  • Records available in English, Spanish
  • English

    This policy brief summarizes evidence from six Campbell systematic reviews of the effects of school-based interventions to improve student behavior. The interventions examined include cognitive behavioral therapy, counseling with at-risk students, and school-wide campaigns targeting destructive mind-sets.

    To access the six included systematic reviews in full, click here.
  • Spanish

    Click on 'Download PDF' on the right to view the policy brief in Spanish.

Additional Info

  • Authors Hugh Waddington
  • Published date 2016-06-08
  • Type of document Policy brief
  • Title Policy brief 3: Programs promoting sustainable agriculture for smallholders
  • Library Image Library Image
  • Records available in English, Spanish
  • English

    This Campbell policy brief summarizes evidence from five Campbell  systematic reviews which examine agricultural interventions including technology, skills and the regulatory environment. The impact of the following interventions is presented: land titling, training and technology, farmer field schools, payment for environmental services and decentralized forest management.

  • Spanish

    Click on 'Download PDF' on the right to view the policy brief in Spanish.

Additional Info

  • Authors Elizabeth Spier, Pia Britto, Terri Pigott, Eugene Roehlkapartain, Michael McCarthy, Yael Kidron, Mengli Song, Peter Scales, Dan Wagner, Julia Lane, Janis Glover
  • Published date 2016-03-23
  • Coordinating group(s) Education, International Development
  • Type of document Review Plain language summary
  • Title Parental, community and familial support interventions to improve children’s literacy in developing countries
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2016.4
  • Records available in English, Hindi, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Limited evidence of effectiveness for home- or community-based child literacy programmes yet some approaches improve outcomes

    There is a wide range of models for out-of-school interventions to improve children’s literacy. Most of these models have not been subject to rigorous evaluation. Support to parents and peers has been largely ineffective in improving literacy, though it has worked in some places. Educational TV has positive effects.

    What did the review study?

    For a majority of the world’s children academic learning is neither occurring at expected rates nor supplying the basic foundational skills necessary to succeed in the 21st century. This review examines the availability of evidence and its findings about the effectiveness of interventions to improve parental, familial, and community support for children’s literacy development in developing countries.

    What is the aim of this review?

    This Campbell systematic review assesses the effectiveness of parental, familial, and community support for children’s literacy development in developing countries. The review summarises findings from 13 studies, of which 10 were used for meta-analysis.

    What studies are included?

    Included studies were published since 2003 with a test of an intervention involving parents, families, or community members with the goal of improving the literacy of children aged 3 to 12 years. The study design had to have a comparison group, and report literacy-related outcomes.

    Thirteen studies are included in the review, covering educational television, interventions that help parents learn how to support their children’s school readiness, and tutoring interventions delivered by peers.

    What were the main findings of the review?

    What models of reading and literacy learning programs have been implemented in homes and communities?

    Many models are widely used in low- and middle-income countries. These include the provision of libraries (standing or mobile) in many countries including Zimbabwe, Kenya, India and Venezuela; local-language publishing in, for example, Cambodia, Sri Lanka, and Zambia; literacy instruction outside schools including the teaching of literacy through religious instruction; the distribution e-readers in countries such as Ghana and Uganda; educational TV and radio; and supporting community members to educate children.

    What models of reading and literacy learning programs implemented in homes and communities in LMICs have empirical evidence regarding their level of effectiveness?

    There is no rigorous evidence of the effectiveness of most of the models being used by governments and NGOs around the world. The exceptions are educational TV and radio, and supporting community members to educate children.

    How effective are these models in improving children’s literacy outcomes?

    Overall, interventions for parent training and of child-to-child tutoring are not effective. Eight out of nine reported outcomes show no significant effects. However, there is considerable variation in the findings, so some approaches may be effective in some contexts.

    Educational television appears to improve literacy with frequent viewing, i.e. three to five times a week, over several months.

    What do the findings in this review mean?

    There are serious gaps in our knowledge. Programs that have worked in some settings should be replicated elsewhere so the contextual factors for success can be identified and understood. There is no evidence for most models used by governments and NGOs, none from one Latin America, and just one study presenting evidence of effects on children aged over seven.

    How up-to-date is this review?

    The review authors searched for studies published until July 2013.

  • Spanish

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

  • Hindi

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

Additional Info

  • Authors David Wilson, Charlotte Gill, Ajima Olaghere, Dave McClure
  • Published date 2016-03-23
  • Coordinating group(s) Crime and Justice
  • Type of document Review Plain language summary
  • Title Juvenile curfew effects on criminal behavior and victimization
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2016.3
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Juvenile curfews are not effective in reducing crime and victimization

    The evidence suggests that juvenile curfews do not reduce crime or victimization.

    What is this review about?

    Curfews restrict youth below a certain age – usually 17 or 18 – from public places during night time. For example, the Prince George’s County, Maryland curfew ordinance restricts youth younger than 17 from public places between 10 p.m. and 5 a.m. on weekdays and between midnight and 5 a.m. on weekends. Sanctions range from a fine that increases with each offense, community service, and restrictions on a youth’s driver’s license. Close to three quarters of US cities have curfews, which are also used in Iceland.

    A juvenile curfew has common sense appeal: keep youth at home during the late night and early morning hours and you will prevent them from committing a crime or being a victim of a crime. In addition, the potential for fines or other sanctions deter youth from being out in a public place during curfew hours.

    This review synthesizes the evidence on the effectiveness of juvenile curfews in reducing criminal behavior and victimization among youth.

    What is the aim of this review?

    This Campbell systematic review assesses the effects of juvenile curfews on crime and victimization. The review summarizes findings from 12 studies.

    What are the main findings of this review?

    What studies are included?

    Included studies test the effect of an official state or local policy intended to restrict or otherwise penalize a juvenile’s presence outside the home during certain times of day. This must have been a general preventive measure directed at all youth within a certain age range and not a sanction imposed on a specific youth.

    Twelve quantitative evaluations of the effects of curfews on youth criminal behavior or victimization are included in the review.

    Do curfews reduce crime and victimization?

    The pattern of evidence suggests that juvenile curfews are ineffective at reducing crime and victimization. The average effect on juvenile crime during curfew hours was slightly positive - that is a slight increase in crime - and close to zero for crime during all hours. Similarly, juvenile victimization also appeared unaffected by the imposition of a curfew ordinance.

    However, all the studies in the review suffer from some limitations that make it difficult to draw firm conclusions. Nonetheless, the lack of any credible evidence in their favor suggests that any effect is likely to be small at best and that curfews are unlikely to be a meaningful solution to juvenile crime and disorder.

    Other studies have suggested curfews may be ineffective as juvenile crime is concentrated in hours before and after school, and that under-resourced police forces focus on more urgent demands than enforcing curfews.

    What do the findings in this review mean?

    Contrary to popular belief, the evidence suggests that juvenile curfews do not produce the expected benefits. The study designs used in this research make it difficult to draw clear conclusions, so more research is needed to replicate the findings. However, many of the biases likely to occur in existing studies would make it more, rather than less, likely that we would conclude curfews are effective. For example, most of these studies were conducted during a time when crime was dropping

    throughout the United States. Therefore, our findings suggest that curfews either don’t have any effect on crime, or the effect is too small to be identified in the research available.

    How up-to-date is this review?

    The search for this review was updated in March 2014.

  • Spanish

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

Additional Info

  • Authors Carol Rivas, Jean Ramsay, Laura Sadowski, Leslie Davidson, Danielle Dunne, Sandra Eldridge, Kelsey Hegarty, Angela Taft, Gene Feder
  • Published date 2016-01-04
  • Coordinating group(s) Social Welfare
  • Type of document Review Plain language summary
  • Title Advocacy interventions to reduce or eliminate violence and promote the physical and psychosocial well-being of women who experience intimate partner abuse
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2016.2
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Limited evidence and limited effects of advocacy to reduce intimate partner violence

    Intensive advocacy may improve everyday life for women in domestic violence shelters and refuges, and reduce physical abuse. There is no clear evidence that intensive advocacy reduces sexual, emotional, or overall abuse, or that it benefits women’s mental health. It is unclear whether brief advocacy is effective.

    What is the review about?

    Partner abuse or domestic violence includes physical, emotional, and sexual abuse; threats; withholding money; causing injury; and long lasting physical and emotional health problems. Active support by trained people, which is called ‘advocacy’, may help women make safety plans, deal with abuse, and access community resources.

    Advocacy may be a stand-alone service, accepting referrals from healthcare providers, or part of a multi-component, and possibly multi-agency, intervention. It may take place in the community, a shelter, or as part of antenatal or other healthcare, and vary in intensity from less than an hour to 80 hours.

    Advocacy may contribute to reducing abuse, empowering women to improve their situation by providing informal counselling and support for safety planning and increasing access to different services.

    What is the aim of this review?

    This Campbell systematic review assesses the effects of advocacy interventions on intimate partner violence and women’s wellbeing. The review summarizes findings from 13 studies.

    What were the main findings of the review?

    What studies are included?

    This review summarizes evidence from 13 clinical trials comparing advocacy for 1,241 abused women with no care or usual care. Most studies followed up on the women for at least a year.

    Does advocacy reduce intimate partner violence and improve women’s wellbeing?

    Physical abuse: After one year, brief advocacy had no effect in two healthcare studies and one community study, but it reduced minor abuse in one antenatal care study. Another antenatal study showed reduced abuse immediately after brief advocacy, but women were also treated for depression, which may have affected results. Two studies provided weak evidence that intensive advocacy reduces physical abuse up to two years after the intervention.

    Sexual abuse was reported in four studies, which found no effects.

    Emotional abuse: One antenatal care study reported reduced emotional abuse at 12 months after advocacy.

    Depression: Brief advocacy prevented depression in abused women attending healthcare services and pregnant women immediately after advocacy. Intensive advocacy did not reduce depression in shelter women followed up at 12 and 24 months. The moderate-to-low quality evidence came mostly from studies with a low risk of bias.

    Quality of life: Three trials of brief advocacy trials no benefit on quality of life. Intensive advocacy showed a weak benefit in two studies in domestic violence shelters and refuges, and a primary care study showed improved motivation to do daily tasks immediately after advocacy.

    What do the results mean?

    Intensive advocacy may improve everyday life for women in domestic violence shelters and refuges in the short term, and reduce physical abuse one to two years after the intervention. There is no clear evidence that intensive advocacy reduces sexual, emotional, or overall abuse, or that it benefits women’s mental health. It is unclear whether brief advocacy is effective, although it may provide short-term mental health benefits and reduce abuse, particularly in pregnant women and those suffering less severe abuse.

    Several studies summarised in this review are potentially biased because of weak study designs. There was little consistency between studies, with variations for advocacy given, the type of benefits measured, and the lengths of follow-up periods, making it hard to combine their results. So it is not possible to be certain how much or which type of advocacy interventions benefit women.

    How up-to-date is this review?

    The search for this review was updated in April 2015.

  • Spanish

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

Additional Info

  • Authors Caio Piza, Tulio Antonio Cravo, Linnet Taylor, Lauro Gonzalez, Isabel Musse, Isabela Furtado, Ana C. Sierra, Samer Abdelnour
  • Published date 2016-01-04
  • Coordinating group(s) International Development
  • Type of document Review Plain language summary
  • Title The impacts of business support services for small and medium enterprises on firm performance in low- and middle-income countries
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2016.1
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Business support services to small and medium enterprises seem to improve firm performance

    Support to small and medium enterprises (SMEs) can improve their revenue and profits, their ability to create jobs, labour productivity and their ability to invest. But these effects are not large, and the cost effectiveness of the interventions not known. The effects on innovation are unclear.

    What is the review about?

    Large amounts of funding are going towards programmes to support small and medium enterprises (SMEs) in low- and middle-income countries in order to increase revenue and profits, generate employment, and, so, create economic growth and reduce poverty.

    The Campbell review summarizes evidence of the impact of these programmes on measures of SME performance including revenues, profits, and productivity, as well as the firms’ ability to generate employment and increase their labour productivity.

    What is the aim of this review?

    This Campbell systematic review assesses the effects of business support services in low- and middle-income countries on firm performance and economic development. The review summarizes findings from 40 studies.

    What were the main findings of the review?

    What studies are included?

    Included studies examine interventions targeted at SMEs (up to 250 employees) involving tax simplification, exports and access to external markets; support for innovation policies; support to local production systems; training and technical assistance, and SME financing and credit guarantee programmes.

    Findings from 40 studies are summarised in the review. These studies present evidence from 18 low- and middle-income countries, with 26 studies analysing programmes in Latin America, six from Asia and five from Africa.

    Do business support services work?

    On average, business support to SMEs seems to improve their performance, their ability to create jobs, their labour productivity and their ability to invest. The effects on innovation are unclear.

    Matching grants, technical assistance and tax simplification programmes can improve firms’ performance and job creation; with technical assistance also likely to improve labour productivity. Export promotion and innovation programmes positively affect exports and innovation, but there is no evidence that they improve performance or job creation.

    However, the effects of the programmes studied are not very large. Most studies do not include the required data to assess if the programmes are cost effective.

    What do the results mean?

    Overall SME support has a positive impact on various measures of firm performance, but with some caveats. Results for the interventions studied are limited due to a lack of evidence. And the evidence available was mainly about programmes in Latin American countries. There is a likelihood of bias in many studies. Most did not report programme implementation costs, so it is not possible to weigh costs against benefits. Research on these programmes in sub-Saharan Africa in particularly encouraged, as this would contribute to the understanding of the role that support to small Businesses may play in development processes there.

    How up-to-date is this review?

    The search for this review was updated in December 2014.

  • Spanish

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

Additional Info

  • Authors Angela Higginson, Kathryn Ham Benier, Yulia Shenderovich, Laura Bedford, Lorraine Mazerolle, Joseph Murray
  • Published date 2015-11-02
  • Coordinating group(s) Crime and Justice, International Development
  • Type of document Review Plain language summary
  • Title Preventive interventions to reduce youth gang violence in low- and middle-income countries
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2015.18
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    There are no rigorous studies of preventive interventions to reduce youth involvement in gangs in low- and middle-income countries

    Youth gang crime poses a serious problem for low and middle-income countries costing billions of dollars in harm, loss of life and social disruption. Preventive interventions are intended to stop crime before it occurs, but there is no evidence as to their effectiveness in low- and middle-income countries.

    What did the review study?

    Youth gangs are commonly associated with high levels of crime and violence in low and middle-income countries. Gangs are often linked to youth trying to overcome extreme disadvantage and marginalisation.

    Preventive interventions are intended to stop crime before it occurs, either by preventing youth from joining gangs or by reducing recidivism by rehabilitating gang members outside of the criminal justice system. This review examines the effectiveness of these preventive interventions in achieving their aims, as well as identifying factors behind successful implementation in low and middle-income countries.

    What is the aim of this review?

    This Campbell systematic review examines why the implementation of preventive interventions to reduce youth involvement in gangs and gang crime may fail or succeed low and middle-income countries. The review summarises findings from four studies conducted in Latin America and the Caribbean. These include findings from field observations and interviews with 63 former gang members in Guatemala, Honduras and El Salvador, 940 respondents in 3 Jamaican communities, 24 participants in Nicaragua and 25 participants in Peru.

    What studies are included?

    Included studies reported on youth gangs with participants aged 10-29 and were located in a low- or middle-income country. Effectiveness studies had to use a valid experimental or non-experimental design.

    There were no studies that met the criteria for an evaluation of effectiveness.

    Four studies evaluating the reasons for implementation success or failure were included in this review. Two of the studies used a purely qualitative study design while the other two used a mixed method study design. All four studies were conducted in Latin America and the Caribbean.

    What are the main results in this review?

    It is not possible to make any conclusions regarding the effectiveness of preventive interventions.

    Four factors may be important for intervention design and implementation:

    1. Having a range of programme components that appeal to youth such as arts and sports.
    2. Active engagement of youths and gang leaders in forming and implementing the programme.
    3. Ensuring continuity of social ties outside the gang which are fragile and may not be preserved after short-term interventions.
    4. Ongoing violence and gang involvement limits successful implementation so needs to be addressed.

    What do the findings in this review mean?

    Preventive gang interventions may be more likely to be successfully implemented where the four factors listed above are present.

    The lack of rigorous evaluations of preventive gang interventions in low and middle-income countries means it is not possible to draw any conclusions about which interventions are most effective in reducing youth involvement in gangs in these contexts. More quantitative and qualitative research on the effectiveness of preventive gang programs is needed in order to determine the best intervention practice.

    How up-to-date is this review?

    The review authors searched for studies published until September 2013.

  • Spanish

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

Additional Info

  • Authors Lana Augustincic Polec, Jennifer Petkovic, Vivian Andrea Welch, Erin Ueffing, Elizabeth Tanjong Ghogomu, Jordi Pardo Pardo, Mark Grabowsky, Amir Attaran, George A. Wells, Peter Tugwell
  • Published date 2015-11-02
  • Coordinating group(s) International Development
  • Type of document Review Plain language summary
  • Title Strategies to increase the ownership and use of insecticide-treated bednets to prevent malaria
  • Library Image Library Image
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2015.17
  • Records available in English, Spanish
  • English

    PLAIN LANGUAGE SUMMARY

    Free bednets increase ownership, and education can increase use

    Economic and educational strategies increase people’s ownership and appropriate use of insecticide-treated bednets (ITNs) in developing countries.

    What did the review study?

    Around 40 percent of the world’s population lives in areas affected by malaria, which is a life-threatening parasitic disease. Insecticide-treated bednets (ITNs) effectively prevent malaria. However, barriers to their use have been identified. This Campbell systematic review assesses the effectiveness of economic and educational strategies for ownership and appropriate use of insecticide-treated bednets in developing countries.

    What is the aim of this review?

    This Campbell systematic review assesses the effectiveness of economic, and educational strategies for ownership and appropriate use of insecticide-treated bednets in developing countries. The review also examines whether changes in ITN ownership and use affect malaria-specific morbidity rates. The review summarises findings from 10 studies, nine of which were conducted in rural Africa and one in rural India.

    What studies are included?

    Included studies tested different strategies to increase the ownership and correct use of ITNs among people living in areas affected by malaria. The study design had to have a comparison group, and include participants with permanent residence in malaria areas.

    Eight cluster randomised-controlled studies together with one randomised controlled and one controlled before-after study were included.

    What are the main results in this review?

    Do economic, and educational strategies increase people’s ownership and appropriate use of ITNs?

    Compared to providing ITNS at full market or a subsidized price, giving away ITNs for free increases the number of people owning an ITN. However, the provision of free ITNs increases their use only slightly or not at all.

    Providing education in the appropriate use of ITNs increases the number of people sleeping under bednets compared to a control group which didn’t receive the education.

    Combining these strategies with unspecified incentives does not increase ITN ownership, leading to little or no differences in their appropriate use. Embedding the promotion of ITNs within specific health- or finance-focused marketing messages only leads to small or no differences in bednet ownership and use.

    Do changes in ITN ownership and use affect malaria-specific morbidity rates?

    There is some evidence of improved malaria-specific morbidities among children and adults as a result of increased ITN ownership and use. However, the evidence supporting this finding is of low certainty and should be interpreted with caution.

    Are there any adverse effects from applying economic, educational or marketing strategies to increase the ownership and appropriate use of ITNs in malaria areas of developing countries?

    None of the included studies measured adverse side effects.

    What do the findings in this review mean?

    Providing ITNs for free can increase bednet ownership in malaria areas in developing countries. Combining this economic strategy with education in the appropriate use of ITNs can increase the number of people sleeping under ITNs.

    Further research is needed to compare the relative effectiveness of different ITN delivery and marketing strategies and of different educational approaches to ensure their appropriate use in malaria-infested areas. Future trials should also examine the sustainability of ITN interventions together with the impact of social and demographic factors on ITN ownership and use.

    How up-to-date is this review?

    The review authors searched for studies published until February 2013.

  • Spanish

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

Additional Info

  • Authors Janice Tripney, Alan Roulstone, Nina Hogrebe, Carol Vigurs, Elena Schmidt, Ruth Stewart
  • Published date 2015-11-02
  • Coordinating group(s) Education, International Development
  • Type of document Review
  • Title Interventions to improve the labour market situation of adults with physical and/or sensory disabilities in low- and middle-income countries
  • See the full review https://onlinelibrary.wiley.com/doi/10.4073/csr.2015.20
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