Search

This guide outlines general issues in searching for studies; describes the main sources of potential studies; and discusses how to plan the search process, design, and carry out search strategies, manage references found during the search process and document and report the search process. [ABSTRACT FROM AUTHOR]

The search methods used in systematic reviews provide the foundation for establishing the body of literature from which conclusions are drawn and recommendations made. Searches should aim to be comprehensive and reporting of search methods should be transparent and reproducible. Campbell Collaboration systematic reviews strive to adhere to the best methodological guidance available for this type of searching. The current work aims to provide an assessment of the conduct and reporting of searches in Campbell Collaboration systematic reviews. Our objectives were to examine how searches are currently conducted in Campbell systematic reviews, how search strategies, search methods and search reporting adhere to the Methodological Expectations of Campbell Collaboration Intervention Reviews (MECCIR) and PRISMA standards, and identify emerging or novel methods used in searching in Campbell systematic reviews. We also investigated the role of information specialists in Campbell systematic reviews. We handsearched the Campbell Systematic Reviews journal tables of contents from January 2017 to March 2024. We included all systematic reviews published since 2017. We excluded other types of evidence synthesis (e.g., evidence and gap maps), updates to systematic reviews when search methods were not changed from the original pre‐2017 review, and systematic reviews that did not conduct their own original searches. We developed a data extraction form in part based on the conduct and reporting items in MECCIR and PRISMA. In addition, we extracted information about the general quality of searches based on the use of Boolean operators, keywords, database syntax and subject headings. Data extraction included information about reporting of sources searched, some aspects of search quality, the use and reporting of supplementary search methods, reporting of the search strategy, the involvement of information specialists, date of the most recent search, and citation of the Campbell search methods guidance. Items were rated as fully, partially or not conducted or reported. We cross‐walked our data extraction items to the 2019 MECCIR standards and 2020 PRISMA guidelines and provide descriptive analyses of the conduct and reporting of searches in Campbell systematic reviews, indicating level of adherence to standards where applicable. We included 111 Campbell systematic reviews across all coordinating groups published since 2017 up to the search date. Almost all (98%) included reviews searched at least two relevant databases and all reported the databases searched. All reviews searched grey literature and most (82%) provided a full list of grey literature sources. Detailed information about databases such as platform and date range coverage was lacking in 16% and 77% of the reviews, respectively. In terms of search strategies, most used Boolean operators, search syntax and phrase searching correctly, but subject headings in databases with controlled vocabulary were used in only about half of the reviews. Most reviews reported at least one full database search strategy (90%), with 63% providing full search strategies for all databases. Most reviews conducted some supplementary searching, most commonly searching the references of included studies, whereas handsearching of journals and forward citation searching were less commonly reported (51% and 62%, respectively). Twenty‐nine percent of reviews involved an information specialist co‐author and about 45% did not mention the involvement of any information specialist. When information specialists were co‐authors, there was a concomitant increase in adherence to many reporting and conduct standards and guidelines, including reporting website URLs, reporting methods for forward citation searching, using database syntax correctly and using subject headings. No longitudinal trends in adherence to conducting and reporting standards were found and the Campbell search methods guidance published in 2017 was cited in only twelve reviews. We also found a median time lag of 20 months between the most recent search and the publication date. In general, the included Campbell systematic reviews searched a wide range of bibliographic databases and grey literature, and conducted at least some supplementary searching such as searching references of included studies or contacting experts. Reporting of mandatory standards was variable with some frequently unreported (e.g., website URLs and database date ranges) and others well reported in most reviews. For example, database search strategies were reported in detail in most reviews. For grey literature, source names were well reported but search strategies were less so. The findings will be used to identify opportunities for advancing current practices in Campbell reviews through updated guidance, peer review processes and author training and support. [ABSTRACT FROM AUTHOR]

Background: Societal changes have led to greater isolation and higher levels of loneliness particularly for older generations. Loneliness is a significant public health challenge leading to increased levels of poor mental health. Depression and anxiety are also increasing in prevalence amongst children and young people. Intergenerational activities are interventions designed to bring together older and younger generations with the purpose of allowing participants to utilise their experiences and skills, and to give participants a chance to experience the pleasure and excitement that occurs with the transmission of knowledge and skills from one generation to another. Intergenerational activities are therefore potential interventions that can address the growing problems associated with loneliness and lack of wellbeing. Objectives: This systematic review aims to examine the impact of intergenerational interventions on the wellbeing and mental health in children and adolescents, and potential harmful effects. It also aims to identify areas for future research as well as key messages for service commissioners. Search Methods: We searched an evidence and gap map published in 2022 (comprehensive searches conducted July 2021 and updated June 2023) to identify randomised controlled trials of intergenerational interventions that report mental health and wellbeing outcomes for children and young people. Selection Criteria: Randomised controlled trials of intergenerational interventions that involved unrelated younger and older people with at least one skipped generation between them and reported mental health or wellbeing outcomes for children and young people were included in this review. Data Collection and Analysis: We used standard methodological procedures expected by The Campbell Collaboration. We conducted data extraction and Cochrane risk of bias assessments in EPPI reviewer. Main Results: While we identified 500 evaluations of intergenerational interventions, where the impact on participating children and/or young people was evaluated this was most often limited to assessing their impact on attitudes to aging. We identified five studies evaluating five different types of intergenerational interventions which included one‐off sessions to ones that spanned a year measuring their impact on the mental health and wellbeing of children and/or young people. The purposes of the interventions differed, which included promoting social skills, preventing harmful behaviour and promoting learning. The ages of children also varied across the five studies, with one targeting younger children, two targeting younger teenagers and two targeting older teenagers. One study included socioeconomically disadvantaged children, and in the other studies the socioeconomic backgrounds of the children and young people were not described. The outcome measures used to evaluate the interventions varied with none of the studies measuring the same outcomes. One study showed improvements in wellbeing measures, and this was an intervention delivered to children in deprived neighbourhoods, where the intervention duration was for a year allowing the development of a greater depth of relationship between the younger and older participants. Four studies found no....... The included studies were at high risk of bias therefore raising uncertainty in the reliability of the findings. Underpinning theories that supported the development of the interventions and explained the mechanisms of effect were poorly described. Authors' Conclusions: The evidence for the effectiveness of intergenerational interventions on the mental health and wellbeing of children and young people is limited and inconclusive. Few evaluations have sought to measure how intergenerational interventions impact children and young people and where this impact is measured the focus is usually limited to attitudes to aging. The evidence that has been collected is too heterogenous to allow synthesis of the findings. The underpinning theories to support their development are poorly described with no follow‐up data to ascertain if benefits are maintained. Intergenerational interventions show promise but researchers have failed to measure how they impact on the mental health and wellbeing of children and young people. This is a serious limitation of the evidence base that needs to be addressed in robust and rigorous evaluations. [ABSTRACT FROM AUTHOR]

Background: Forwards citation searching is a valuable method for finding relevant studies in reviews where concepts are not clearly defined. Scopus and Web of Science can both be used for forwards citation searching but there is little evidence comparing the resources for this purpose. Method: 104 source records relevant to a scoping review of implementation and dissemination strategies in dementia care were checked for inclusion on Web of Science and Scopus. The number of citing references was recorded. Where citing references appeared unique to one of the resources, they were checked for inclusion on the other resource to assess the performance of citation links. Results: 1397 citing references were returned by Scopus and 1010 were returned by Web of Science. For the unique citing references returned by Web of Science (n = 52), 36 were subsequently found to be on Scopus but had failed to be picked up as citing a source record. Of the unique citing references returned by Scopus (n = 355), 83 were found to be on Web of Science but had failed to be picked up as citing a source record. 26 additional relevant records were identified for the review by forwards citation searching. All were found on Scopus; six would have been missed by searching Web of Science alone. Conclusion: Citation searching using Scopus alone would have found all additional relevant studies for the review. Both Scopus and Web of Science failed to return all citing references from the source records, even where they were present on the database, indicating poor links between citations.

Background: The search for studies for a systematic review should be conducted systematically and reported transparently to facilitate reproduction. This study aimed to report on the conduct and reporting of backward citation searching (ie, checking reference lists) and forward citation searching in a cross section of Cochrane reviews. Citation searching uses the citation network surrounding a source study to identify additional studies. Methods: Cochrane reviews were identified by searching the Cochrane Database of Systematic Reviews using the wildcard symbol and date limiting to the 3-month period November 2016 to January 2017. Cochrane reviews thus identified were screened for mention of citation searching. Descriptive detail on the conduct and reporting of citation searching was captured in data extraction forms and described and evaluated. Results: Two hundred fifteen Cochrane reviews were identified. One hundred seventy-two reviews reported backward citation searching, and 18 reviews reported forward citation searching. Web of Science was the most frequently reported citation index. The studies used for backward citation searching consisted mainly of studies meeting the inclusion criteria. One-third of reviews that reported forward citation searching used selected studies of importance. Reporting of citation searching was compliant with the Methodological Expectations of Cochrane Intervention Reviews (MECIR) standards, but full transparency requires additional detail that only a minority of reviews reported. Conclusion: The conduct of backward citation searching was more uniform than forward citation searching. This might be due to lack of MECIR guidance for forward citation searching. Reporting was generally compliant with MECIR, but this is not always sufficient to ensure full transparency.

Background: Qualitative research in dementia improves understanding of the experience of people affected by dementia. Searching databases for qualitative studies is problematic. Qualitative-specific search strategies might help with locating studies. Objective: To examine the effectiveness (sensitivity and precision) of 5 qualitative strategies on locating qualitative research studies in dementia in 4 major databases (MEDLINE, EMBASE, PsycINFO, and CINAHL). Methods: Qualitative dementia studies were checked for inclusion on MEDLINE, EMBASE, PsycINFO, and CINAHL. Five qualitative search strategies (subject headings, simple free-text terms, complex free-text terms, and 2 broad-based strategies) were tested for study retrieval. Specificity, precision and number needed to read were calculated. Results: Two hundred fourteen qualitative studies in dementia were included. PsycINFO and CINAHL held the most qualitative studies out the 4 databases studied (N = 171 and 166, respectively) and both held unique records (N = 14 and 7, respectively). The controlled vocabulary strategy in CINAHL returned 96% (N = 192) of studies held; by contrast, controlled vocabulary in PsycINFO returned 7% (N = 13) of studies held. The broad-based strategies returned more studies (93-99%) than the other free-text strategies (22-82%). Precision ranged from 0.061 to 0.004 resulting in a number needed to read to obtain 1 relevant study ranging from 16 (simple free-text search in CINAHL) to 239 (broad-based search in EMBASE). Conclusion: Qualitative search strategies using 3 broad terms were more sensitive than long complex searches. The controlled vocabulary for qualitative research in CINAHL was particularly effective. Furthermore, results indicate that MEDLINE and EMBASE offer little benefit for locating qualitative dementia research if CINAHL and PSYCINFO are also searched.

Background: Early detection of autism spectrum disorder (ASD) has the potential to significantly reduce the impact of the condition, however previous reviews have found little evidence to support screening programs for ASD in young children. Methods: We conducted a review with the aim of updating evidence on 3 aspects: (a) diagnostic stability of ASD in young children; (b) accuracy of ASD screening tools in young children; and (c) the benefits of early interventions in screen-detected young children with ASD. Results: A total of 33 studies were included in our review. Five studies looking at diagnostic stability reported estimates ranging from 71.9% to 100%, however the majority only included a follow-up of 24 months and all studies raised concerns regarding the risk of bias due particularly to lack of blinding, sample size, and patient flow. A total of 25 studies, reported in 26 articles, were identified that reported accuracy data on 11 screening tools. Most of the reports were concerned with versions of M-CHAT, reporting sensitivity estimates from 0.67 to 1.0; however, many of these were deemed to be of high risk of bias due to lack of blinding and follow-up. Four studies reported on early interventions in screen-detected children; however, the majority did not find significant improvements on the relevant outcomes. Conclusions: Overall, the evidence on screening for ASD in young children captured by this review is not conclusive regarding the 3 aspects of screening in this population. Future studies should attempt to ensure blinded diagnostic assessments, include longer follow-up periods and limit attrition. [ABSTRACT FROM AUTHOR]

Background: A challenge when using Google Search to identify studies for a systematic review is managing the high number of results, which can number in the hundreds of thousands or even more. Studies and guidance on web searching suggest limiting the screening process, e.g. to the first 100 results. Objectives: Our objective in this case study is to demonstrate an alternative approach to screening the results retrieved by Google Search which is based on our experience that the viewable number of results is often far fewer than the estimated number calculated by the search engine. Methods: We screened the results of three searches of Google Search using our approach, which involves increasing the number of results displayed per page from 10 to the maximum of 100. We then calculated the viewable number of results and compared this with the estimated number. Results: The mean of the estimated number of results for the three searches was 569,454,000. The mean of the viewable number results was 463 (0.00008% of the mean of the estimated number of results). Conclusion: Our findings challenge the commonly reported view that the number of results retrieved when using Google Search is too high to screen in full. [ABSTRACT FROM AUTHOR]

Non-pharmacological interventions for attention-deficit/hyperactivity disorder are useful treatments, but it is unclear how effective school-based interventions are for a range of outcomes and which features of interventions are most effective. This paper systematically reviews randomised controlled trial evidence of the effectiveness of interventions for children with ADHD in school settings. Three methods of synthesis were used to explore the effectiveness of interventions, whether certain types of interventions are more effective than others and which components of interventions lead to effective academic outcomes. Twenty-eight studies (n = 1807) were included in the review. Eight types of interventions were evaluated and a range of different ADHD symptoms, difficulties and school outcomes were assessed across studies. Meta-analyses demonstrated beneficial effects for interventions that combine multiple features (median effect size g = 0.37, interquartile range 0.32, range 0.09-1.13) and suggest some promise for daily report card interventions (median g = 0.62, IQR = 0.25, range 0.13-1.62). Meta-regression analyses did not give a consistent message regarding which types of interventions were more effective than others. Finally, qualitative comparative analysis demonstrated that self-regulation and one-to-one intervention delivery were important components of interventions that were effective for academic outcomes. These two components were not sufficient though; when they appeared with personalisation for individual recipients and delivery in the classroom, or when interventions did not aim to improve child relationships, interventions were effective. This review provides updated information about the effectiveness of non-pharmacological interventions specific to school settings and gives tentative messages about important features of these interventions for academic outcomes.

Objectives: To systematically review the accuracy of artificial intelligence (AI)-based systems for grading of fundus images in diabetic retinopathy (DR) screening. Methods: We searched MEDLINE, EMBASE, the Cochrane Library and the ClinicalTrials.gov from 1st January 2000 to 27th August 2021. Accuracy studies published in English were included if they met the pre-specified inclusion criteria. Selection of studies for inclusion, data extraction and quality assessment were conducted by one author with a second reviewer independently screening and checking 20% of titles. Results were analysed narratively. Results: Forty-three studies evaluating 15 deep learning (DL) and 4 machine learning (ML) systems were included. Nine systems were evaluated in a single study each. Most studies were judged to be at high or unclear risk of bias in at least one QUADAS-2 domain. Sensitivity for referable DR and higher grades was ≥85% while specificity varied and was <80% for all ML systems and in 6/31 studies evaluating DL systems. Studies reported high accuracy for detection of ungradable images, but the latter were analysed and reported inconsistently. Seven studies reported that AI was more sensitive but less specific than human graders. Conclusions: AI-based systems are more sensitive than human graders and could be safe to use in clinical practice but have variable specificity. However, for many systems evidence is limited, at high risk of bias and may not generalise across settings. Therefore, pre-implementation assessment in the target clinical pathway is essential to obtain reliable and applicable accuracy estimates. [ABSTRACT FROM AUTHOR]