Objectives To conduct a meta-analytic review of selective and indicated mentoring interventions for effects for youth at risk on delinquency and key associated outcomes (aggression, drug use, academic functioning). We also undertook the first systematic evaluation of intervention implementation features and organization and tested for effects of theorized key processes of mentor program effects. Methods Campbell Collaboration review inclusion criteria and procedures were used to search and evaluate the literature. Criteria included a sample defined as at-risk for delinquency due to individual behavior such as aggression or conduct problems or environmental characteristics such as residence in high-crime community. Studies were required to be random assignment or strong quasi-experimental design. Of 163 identified studies published 1970 - 2011, 46 met criteria for inclusion. Results Mean effects sizes were significant and positive for each outcome category (ranging form d =.11 for Academic Achievement to d = .29 for Aggression). Heterogeneity in effect sizes was noted for all four outcomes. Stronger effects resulted when mentor motivation was professional development but not by other implementation features. Significant improvements in effects were found when advocacy and emotional support mentoring processes were emphasized. Conclusions This popular approach has significant impact on delinquency and associated outcomes for youth at-risk for delinquency. While evidencing some features may relate to effects, the body of literature is remarkably lacking in details about specific program features and procedures. This persistent state of limited reporting seriously impedes understanding about how mentoring is beneficial and ability to maximize its utility.

The Campbell Collaboration was founded on the principle that systematic reviews on the effects of interventions will inform and help improve policy and services. Campbell offers editorial and methodological support to review authors throughout the process of producing a systematic review. A number of Campbell's editors, librarians, methodologists and external peer reviewers contribute. Plain language summaryInterventions to reduce homelessness and improve housing stability are effectiveThere are large numbers of homeless people around the world. Interventions to address homelessness seem to be effective, though better quality evidence is required. What is this review about?There are large numbers of homeless people around the world. Recent estimates are over 500,000 people in the USA, 100,000 in Australia and 30,000 in Sweden. Efforts to combat homelessness have been made on national levels as well as at local government levels.This review assesses the effectiveness of interventions combining housing and case management as a means to reduce homelessness and increase residential stability for individuals who are homeless, or at risk of becoming homeless. What is the aim of this review?This Campbell systematic review examines the effectiveness of interventions to reduce homelessness and increase residential stability for individuals who are homeless, or at risk of becoming homeless. Forty-three studies were included in the review, 37 of which are from the USA. What studies are included?Included studies were randomized controlled trials of interventions for individuals who were already, or at-risk of becoming, homeless, and which measured impact on homelessness or housing stability with follow-up of at least one year.A total of 43 studies were included. The majority of the studies (37) were conducted in the United States, with three from the United Kingdom and one each from Australia, Canada, and Denmark. 6The Campbell Collaboration | www.campbellcollaboration.org What are the main findings of this review?Included interventions perform better than the usual services at reducing homelessness or improving housing stability in all comparisons. These interventions are: These interventions seem to have similar beneficial effects, so it is unclear which of these is best with respect to reducing homelessness and increasing housing stability. What do the findings of this review mean?A range of housing programs and case management interventions appear to reduce homelessness and improve housing stability, compared to usual services.However, there is uncertainty in this finding as most the studies have risk of bias due to poor reporting, lack of blinding, or poor randomization or allocation concealment of participants. In addition to the general need for better conducted and reported studies, there are specific gaps in the research with respect to: 1) disadvantaged youth; 2) abstinence-contingent housing with case management or day treatment; 3) non-abstinence contingent housing comparing group vs independent living; 4) Hous...

Mentoring is one of the most commonly‐used interventions to prevent, divert, and remediate youth engaged in, or thought to be at risk for delinquent behavior, school failure, aggression, or other antisocial behavior. We conducted a meta‐analytic review of selective and indicated mentoring interventions that have been evaluated for their effects on delinquency outcomes for youth (e.g., arrest or conviction as a delinquent, self‐reported involvement) and key associated outcomes (aggression, drug use, academic functioning). Of 112 identified studies reported published between 1970 and 2005, 39 met criteria for inclusion. Mean effects sizes were significant and positive for each outcome category. Effects were largest (still moderate by Cohen's differentiation) for delinquency and aggression. However, these categories also showed the most heterogeneity across studies. The obtained patterns of effects suggest mentoring may be valuable for those at‐risk or already involved in delinquency and for associated outcomes. Moderator analyses found stronger effects in randomised controlled trials compared to quasi‐experimental studies, for studies where emotional support was a key process involved in mentoring, and where professional development was a motivation for mentors. However, the collected set of studies are less informative than expected with quite limited detail in studies about what comprised mentoring activity and key implementation characteristics. This limitation encourages caution particularly in interpreting the moderated effects. These findings add to the longstanding calls for more careful design and testing of mentoring efforts to provide the needed specificity to guide effective practice of this popular approach. Abstract BackgroundIn recent years, mentoring has drawn substantial interest from policymakers, intervention theorists, and those interested in identifying promising and useful evidence‐based approaches to interventions for criminal justice and child welfare outcomes (Grossman & Tierney, 1998; Jekliek et al., 2002). Mentoring is one of the most commonly‐used interventions to prevent, divert, and remediate youth engaged in, or thought to be at risk for, delinquent behavior, school failure, aggression, or other antisocial behavior (DuBois, Holloway, Valentine, & Cooper, 2002). One account lists over 4500 organizations within the United States that use mentoring to promote youth wellbeing and reduce risk (Rhodes, 2002). Definitions of mentoring vary, but there are common elements. For the purpose of this review, mentoring was defined by the following 4 characteristics: 1) interaction between two individuals over an extended period of time, 2) inequality of experience, knowledge, or power between the mentor and mentee (recipient), with the mentor possessing the greater share, 3) the mentee is in a position to imitate and benefit from the knowledge, skill, ability, or experience of the mentor, 4) the absence of the role inequality that typifies other helping relationships and is marked by professional tr...

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