Conducting umbrella reviews

In this article, Lazaros Belbasis and colleagues explain the rationale for umbrella reviews and the key steps involved in conducting an umbrella review, using a working example

Mediterranean diet and risk of breast cancer: An umbrella review

Background The Mediterranean Diet (MedDiet) is a healthy dietary pattern which has been related to a lower risk of certain chronic diseases, such as some cancers. However, its role in breast cancer development remains unclear. This umbrella review aims to summarize the highest available evidence on MedDiet and breast cancer risk. Methods Pubmed, Web of Science, and Scopus electronic platforms were searched for relevant systematic reviews and meta-analyses. The selection criteria included systematic reviews with or without meta-analysis including women aged 18 years or older which evaluated the adherence to a MedDiet as the exposure and incidence of breast cancer as the outcome variable. Overlapping and quality of the reviews using AMSTAR-2 tool were independently assessed by two authors. Results Five systematic reviews and six systematic reviews with meta-analysis were included. Overall, 4 systematic reviews – two with and two without meta-analysis – were rated as of high quality. An inverse association was found in 5 of the 9 reviews which evaluated the role of MedDiet on the risk of total breast cancer. The meta-analyses showed moderate-high heterogeneity. The risk reduction seemed to be more consistent among postmenopausal women. No association was found for MedDiet among premenopausal women. Conclusions The results of this umbrella review suggest that adherence to a MedDiet pattern had a protective effect on the risk of breast cancer, especially for postmenopausal breast cancer. The stratification of breast cancer cases and conducting high-quality reviews are aspects needed to overcome the current results’ heterogeneity and to improve knowledge in this field.Funding for open access charge: Universidad de Málaga / CBU

Mediterranean diet and risk of breast cancer: An umbrella review

Supplementary data to this article can be found online at https://doi.org/10.1016/j.clnu.2023.02.012Background: The Mediterranean Diet (MedDiet) is a healthy dietary pattern which has been related to a lower risk of certain chronic diseases, such as some cancers. However, its role in breast cancer development remains unclear. This umbrella review aims to summarize the highest available evidence on MedDiet and breast cancer risk. Methods: Pubmed, Web of Science, and Scopus electronic platforms were searched for relevant systematic reviews and meta-analyses. The selection criteria included systematic reviews with or without meta-analysis including women aged 18 years or older which evaluated the adherence to a MedDiet as the exposure and incidence of breast cancer as the outcome variable. Overlapping and quality of the reviews using AMSTAR-2 tool were independently assessed by two authors. Results: Five systematic reviews and six systematic reviews with meta-analysis were included. Overall, 4 systematic reviews e two with and two without meta-analysis e were rated as of high quality. An inverse association was found in 5 of the 9 reviews which evaluated the role of MedDiet on the risk of total breast cancer. The meta-analyses showed moderate-high heterogeneity. The risk reduction seemed to be more consistent among postmenopausal women. No association was found for MedDiet among premenopausal women. Conclusions: The results of this umbrella review suggest that adherence to a MedDiet pattern had a protective effect on the risk of breast cancer, especially for postmenopausal breast cancer. The stratification of breast cancer cases and conducting high-quality reviews are aspects needed to overcome the current results’ heterogeneity and to improve knowledge in this fieldConsejería de Transformación Económica, Industria, Con- ocimiento y Universidades of the Junta de Andalucía for the grant received (PREDOC_00551)Universidad de Málaga / Consorcio de Bibliotecas Universitarias de Andalucía (CBUA) for funding the Open Access fees for the publicatio

Systematic reviews: guidance relevant for studies of older people

Systematic reviews and meta-analyses are increasingly common. This article aims to provide guidance for people conducting systematic reviews relevant to the healthcare of older people. An awareness of these issues will also help people reading systematic reviews to determine whether the results will influence their clinical practice. It is essential that systematic reviews are performed by a team which includes the required technical and clinical expertise. Those performing reviews for the first time should ensure they have appropriate training and support. They must be planned and performed in a transparent and methodologically robust way: guidelines are available. The protocol should be written—and if possible published—before starting the review. Geriatricians will be interested in a table of baseline characteristics, which will help to determine if the studied samples or populations are similar to their patients. Reviews of studies of older people should consider how they will manage issues such as different age cut-offs; non-specific presentations; multiple predictors and outcomes; potential biases and confounders. Systematic reviews and meta-analyses may provide evidence to improve older people's care, or determine where new evidence is required. Newer methodologies, such as meta-analyses of individual level data, network meta-analyses and umbrella reviews, and realist synthesis, may improve the reliability and clinical utility of systematic reviews

Selecting and implementing overview methods: implications from five exemplar overviews

This is the final version of the article. Available from BioMed Central via the DOI in this record.Background Overviews of systematic reviews are an increasingly popular method of evidence synthesis; there is a lack of clear guidance for completing overviews and a number of methodological challenges. At the UK Cochrane Symposium 2016, methodological challenges of five overviews were explored. Using data from these five overviews, practical implications to support methodological decision making of authors writing protocols for future overviews are proposed. Methods Methods, and their justification, from the five exemplar overviews were tabulated and compared with areas of debate identified within current literature. Key methodological challenges and implications for development of overview protocols were generated and synthesised into a list, discussed and refined until there was consensus. Results Methodological features of three Cochrane overviews, one overview of diagnostic test accuracy and one mixed methods overview have been summarised. Methods of selection of reviews and data extraction were similar. Either the AMSTAR or ROBIS tool was used to assess quality of included reviews. The GRADE approach was most commonly used to assess quality of evidence within the reviews. Eight key methodological challenges were identified from the exemplar overviews. There was good agreement between our findings and emerging areas of debate within a recent published synthesis. Implications for development of protocols for future overviews were identified. Conclusions Overviews are a relatively new methodological innovation, and there are currently substantial variations in the methodological approaches used within different overviews. There are considerable methodological challenges for which optimal solutions are not necessarily yet known. Lessons learnt from five exemplar overviews highlight a number of methodological decisions which may be beneficial to consider during the development of an overview protocol.The overview conducted by Pollock [19] was supported by a project grant from the Chief Scientist Office of the Scottish Government. The overview conducted by McClurg [21] was supported by a project grant by the Physiotherapy Research Foundation. The overview by Hunt [22] was supported as part of doctoral programme funding by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC). The overview conducted by Estcourt [20] was supported by an NIHR Cochrane Programme Grant for the Safe and Appropriate Use of Blood Components. The overview conducted by Brunton [23] was commissioned by the Department of Health as part of an ongoing programme of work on health policy research synthesis. Alex Pollock is employed by the Nursing, Midwifery and Allied Health Professions (NMAHP) Research Unit, which is supported by the Chief Scientist Office of the Scottish Government. Pauline Campbell is supported by the Chief Nurses Office of the Scottish Government

Methodological and terminological issues in animal-assisted interventions: An umbrella review of systematic reviews

Recently, animal-assisted interventions (AAIs), which are defined as psychological, educational, and rehabilitation support activities, have become widespread in different contexts. For many years, they have been a subject of interest in the international scientific community and are at the center of an important discussion regarding their effectiveness and the most appropriate practices for their realization. We carried out an umbrella review (UR) of systematic reviews (SRs), created for the purpose of exploring the literature and aimed at deepening the terminological and methodological aspects of AAIs. It is created by exploring the online databases PubMed, Google Scholar, and Cochrane Library. The SRs present in the high-impact indexed search engines Web of Sciences and Scopus are selected. After screening, we selected 15 SRs that met the inclusion criteria. All papers complained of the poor quality of AAIs; some considered articles containing interventions that did not always correspond to the terminology they have explored and whose operating practices were not always comparable. This stresses the need for the development and consequent diffusion of not only operational protocols, but also research protocols which provide for the homogeneous use of universally recognized terminologies, thus facilitating the study, deepening, and comparison between the numerous experiences described

Credibility of subgroup analyses by socioeconomic status in public health intervention evaluations:An underappreciated problem?

There is increasing interest amongst researchers and policy makers in identifying the effect of public health interventions on health inequalities by socioeconomic status (SES). This issue is typically addressed in evaluation studies through subgroup analyses, where researchers test whether the effect of an intervention differs according to the socioeconomic status of participants. The credibility of such analyses is therefore crucial when making judgements about how an intervention is likely to affect health inequalities, although this issue appears to be rarely considered within public health. The aim of this study was therefore to assess the credibility of subgroup analyses in published evaluations of public health interventions. An established set of 10 credibility criteria for subgroup analyses was applied to a purposively sampled set of 21 evaluation studies, the majority of which focussed on healthy eating interventions, which reported differential intervention effects by SES. While the majority of these studies were found to be otherwise of relatively high quality methodologically, only 8 of the 21 studies met at least 6 of the 10 credibility criteria for subgroup analysis. These findings suggest that the credibility of subgroup analyses conducted within evaluations of public health interventions’ impact on health inequalities may be an underappreciated problem. Keywords: Health inequalities, Health inequities, Equity and public health interventions, Policy impact by socioeconomic statu

Gender differences in the impact of population-level alcohol policy interventions: evidence synthesis of systematic reviews

Background: Consistent review-level evidence supports the effectiveness of population-level alcohol policies in reducing alcohol-related harms. Such policies interact with well-established social, cultural and biological differences in how men and women perceive, relate to and use alcohol, and with wider inequalities, in ways which may give rise to gender differences in policy effectiveness.  Aims: To examine the extent to which gender-specific data and analyses were considered in, and are available from, systematic reviews of population-level alcohol policy interventions, and where possible, to conduct a narrative synthesis of relevant data.  Methods: A prior systematic ‘review of reviews’ of population level alcohol interventions 2002-2012 was updated to May 2014, all gender-relevant data extracted, and the level and quality of gender reporting assessed. A narrative synthesis of extracted findings was conducted.  Results: Sixty-three systematic reviews, covering ten policy areas, were included. Five reviews (8%) consistently provided information on baseline participation by gender for each individual study in the review and twenty-nine (46%) reported some gender-specific information on the impact of the policies under consideration. Specific findings include evidence of possible gender differences in the impact of and exposure to alcohol marketing, and a failure to consider potential unintended consequences and harm to others in most reviews.  Conclusions: Gender is poorly reported in systematic reviews of population-level interventions to reduce alcohol-related harm, hindering assessment of the intended and unintended effects of such policies on women and men

Historical review of “umbrella supervision” by the Board of Governors of the Federal Reserve System

The article reviews legislative history and supervisory practices related to bank holding companies with a view toward understanding what Congress meant by referring to the Board of Governors of the Federal Reserve System as the “umbrella supervisor” in the Gramm-Leach-Bliley Act. The first part of the article looks at the historical development of bank holding company law and regulation, which laid the foundation for the current practice of umbrella supervision. The second part of the article provides answers to questions related to the Board’s current role as umbrella supervisor: What does “umbrella supervision” mean, and is it different from “consolidated supervision”? How does the GLB Act limit the Board's authority and practice and when did the Board obtain all of the legal authority to allow it to practice umbrella supervision?Bank holding companies ; Bank supervision ; Gramm-Leach-Bliley Act ; Banking law

PRECEPT: an evidence assessment framework for infectious disease epidemiology, prevention and control

Decisions in public health should be based on the best available evidence, reviewed and appraised using a rigorous and transparent methodology. The Project on a Framework for Rating Evidence in Public Health (PRECEPT) defined a methodology for evaluating and grading evidence in infectious disease epidemiology, prevention and control that takes different domains and question types into consideration. The methodology rates evidence in four domains: disease burden, risk factors, diagnostics and intervention. The framework guiding it has four steps going from overarching questions to an evidence statement. In step 1, approaches for identifying relevant key areas and developing specific questions to guide systematic evidence searches are described. In step 2, methodological guidance for conducting systematic reviews is provided; 15 study quality appraisal tools are proposed and an algorithm is given for matching a given study design with a tool. In step 3, a standardised evidence-grading scheme using the Grading of Recommendations Assessment, Development and Evaluation Working Group (GRADE) methodology is provided, whereby findings are documented in evidence profiles. Step 4 consists of preparing a narrative evidence summary. Users of this framework should be able to evaluate and grade scientific evidence from the four domains in a transparent and reproducible way.Funding Agencies|European Centre for Disease Prevention and Control (ECDC) [2012/040, 2014/008]</p