[The PRISMA 2020 statement: an updated guideline for reporting systematic reviewsDeclaración PRISMA 2020: una guía actualizada para la publicación de revisiones sistemáticas]. / A declaração PRISMA 2020: diretriz atualizada para relatar revisões sistemáticas.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews.

La declaración PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses), publicada en 2009, se diseñó para ayudar a los autores de revisiones sistemáticas a documentar de manera transparente el porqué de la revisión, qué hicieron los autores y qué encontraron. Durante la última década, ha habido muchos avances en la metodología y terminología de las revisiones sistemáticas, lo que ha requerido una actualización de esta guía. La declaración PRISMA 2020 sustituye a la declaración de 2009 e incluye una nueva guía de presentación de las publicaciones que refleja los avances en los métodos para identificar, seleccionar, evaluar y sintetizar estudios. La estructura y la presentación de los ítems ha sido modificada para facilitar su implementación. En este artículo, presentamos la lista de verificación PRISMA 2020 con 27 ítems, y una lista de verificación ampliada que detalla las recomendaciones en la publicación de cada ítem, la lista de verificación del resumen estructurado PRISMA 2020 y el diagrama de flujo revisado para revisiones sistemáticas.

The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.

Matthew Page and co-authors describe PRISMA 2020, an updated reporting guideline for systematic reviews and meta-analyses.

Random-effects meta-analysis of inconsistent effects: a time for change.

A primary goal of meta-analysis is to improve the estimation of treatment effects by pooling results of similar studies. This article explains how the most widely used method for pooling heterogeneous studies--the Der Simonian-Laird (DL) estimator--can produce biased estimates with falsely high precision. A classic example is presented to show that use of the DL estimator can lead to erroneous conclusions. Particular problems with the DL estimator are discussed, and several alternative methods for summarizing heterogeneous evidence are presented. The authors support replacing universal use of the DL estimator with analyses based on a critical synthesis that recognizes the uncertainty in the evidence,focuses on describing and explaining the probable sources of variation in the evidence, and uses random-effects estimates that provide more accurate confidence limits than the DL estimator.

Handling of rescue and missing data affects synthesis and interpretation of evidence: the sodium-glucose cotransporter 2 inhibitor example.

Confidence in evidence summarized in meta-analyses depends on the strength of the underlying studies. This inherent limitation of syntheses appears in the case of a meta-analysis of sodium-glucose cotransporter 2 inhibitors for the treatment of type 2 diabetes because many of the pertinent randomized trials did not handle patient dropout and "rescue" medication properly. Repudiated statistical methods, such as last observation carried forward, and unsophisticated methods for handling postrescue data produce unreliable summary estimates. Future reports of randomized studies and meta-analyses of those studies must focus on posing precise questions about the treatment effect of interest and then implement appropriate statistical methods to account for missing data, patient dropout, and use of rescue medication.

Updating guidance for reporting systematic reviews: development of the PRISMA 2020 statement.

OBJECTIVES: To describe the processes used to update the PRISMA 2009 statement for reporting systematic reviews, present results of a survey conducted to inform the update, summarize decisions made at the PRISMA update meeting, and describe and justify changes made to the guideline. METHODS: We reviewed 60 documents with reporting guidance for systematic reviews to generate suggested modifications to the PRISMA 2009 statement. We invited 220 systematic review methodologists and journal editors to complete a survey about the suggested modifications. The results of these projects were discussed at a 21-member in-person meeting. Following the meeting, we drafted the PRISMA 2020 statement and refined it based on feedback from co-authors and a convenience sample of 15 systematic reviewers. RESULTS: The review of 60 documents revealed that all topics addressed by the PRISMA 2009 statement could be modified. Of the 110 survey respondents, more than 66% recommended keeping six of the original checklist items as they were and modifying 15 of them using wording suggested by us. Attendees at the in-person meeting supported the revised wording for several items but suggested rewording for most to enhance clarity, and further refinements were made over six drafts of the guideline. CONCLUSIONS: The PRISMA 2020 statement consists of updated reporting guidance for systematic reviews. We hope that providing this detailed description of the development process will enhance the acceptance and uptake of the guideline and assist those developing and updating future reporting guidelines.

The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. / Declaración PRISMA 2020: una guía actualizada para la publicación de revisiones sistemáticas.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews. Full English text available from:www.revespcardiol.org/en.

The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews.

The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.

The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement, published in 2009, was designed to help systematic reviewers transparently report why the review was done, what the authors did, and what they found. Over the past decade, advances in systematic review methodology and terminology have necessitated an update to the guideline. The PRISMA 2020 statement replaces the 2009 statement and includes new reporting guidance that reflects advances in methods to identify, select, appraise, and synthesise studies. The structure and presentation of the items have been modified to facilitate implementation. In this article, we present the PRISMA 2020 27-item checklist, an expanded checklist that details reporting recommendations for each item, the PRISMA 2020 abstract checklist, and the revised flow diagrams for original and updated reviews.

Mapping of reporting guidance for systematic reviews and meta-analyses generated a comprehensive item bank for future reporting guidelines.

OBJECTIVES: The aim of the study was to generate a comprehensive bank of systematic review (SR) reporting items to inform an update of the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2009 statement. METHODS: We searched the Enhancing the QUAlity and Transparency Of health Research Network library in May 2019 to identify all reporting guidelines for SRs that were published after 2009, regardless of the scope of the guideline. We also conducted a selective review of four guidance manuals for SRs, three tools for assessing the risk of bias in SRs, six meta-research studies evaluating the reporting quality of SRs using a tailored checklist, and five reporting guidelines for other study designs. One author screened and selected sources for inclusion, extracted reporting guidance from sources, and mapped guidance against the PRISMA 2009 checklist items. RESULTS: We included 60 sources providing guidance on reporting of SRs and meta-analyses. From these, we collated a list of 221 unique reporting items. Items were categorized into title (four items), abstract (10 items), introduction (12 items), methods (111 items), results (61 items), discussion (12 items), funding and conflicts of interest (four items), administrative information (three items), and data availability (four items). This exercise generated 175 reporting items that could be added to the guidance in the PRISMA 2009 statement. CONCLUSION: Generation of a comprehensive item bank through review and mapping of the literature facilitates identification of missing items and those needing modification, which may not otherwise be identified by the guideline development team or from other activities commonly used to develop reporting guidelines.

REPRINT OF: Current Methods of the U.S. Preventive Services Task Force: A Review of the Process.

Editor's Note: This article is a reprint of a previously published article. For citation purposes, please use the original publication details: Harris RP, Helfand M, Woolf SH, et al. Current methods of the U.S. Preventive Services Task Force: a review of the process. Am J Prev Med. 2001;20(3S):21-35. The U.S. Preventive Services Task Force (USPSTF/Task Force) represents one of several efforts to take a more evidence-based approach to the development of clinical practice guidelines. As methods have matured for assembling and reviewing evidence and for translating evidence into guidelines, so too have the methods of the USPSTF. This paper summarizes the current methods of the third USPSTF, supported by the Agency for Healthcare Research and Quality (AHRQ) and two of the AHRQ Evidence-based Practice Centers (EPCs). The Task Force limits the topics it reviews to those conditions that cause a large burden of suffering to society and that also have available a potentially effective preventive service. It focuses its reviews on the questions and evidence most critical to making a recommendation. It uses analytic frameworks to specify the linkages and key questions connecting the preventive service with health outcomes. These linkages, together with explicit inclusion criteria, guide the literature searches for admissible evidence. Once assembled, admissible evidence is reviewed at three strata: (1) the individual study, (2) the body of evidence concerning a single linkage in the analytic framework, and (3) the body of evidence concerning the entire preventive service. For each stratum, the Task Force uses explicit criteria as general guidelines to assign one of three grades of evidence: good, fair, or poor. Good or fair quality evidence for the entire preventive service must include studies of sufficient design and quality to provide an unbroken chain of evidence-supported linkages, generalizable to the general primary care population, that connect the preventive service with health outcomes. Poor evidence contains a formidable break in the evidence chain such that the connection between the preventive service and health outcomes is uncertain. For services supported by overall good or fair evidence, the Task Force uses outcomes tables to help categorize the magnitude of benefits, harms, and net benefit from implementation of the preventive service into one of four categories: substantial, moderate, small, or zero/negative. The Task Force uses its assessment of the evidence and magnitude of net benefit to make a recommendation, coded as a letter: from A (strongly recommended) to D (recommend against). It gives an I recommendation in situations in which the evidence is insufficient to determine net benefit. The third Task Force and the EPCs will continue to examine a variety of methodologic issues and document work group progress in future communications.

[Strengthening the reporting of observational studies in epidemiology (STROBE): explanation and elaboration]. / Mejorar la comunicación de estudios observacionales en epidemiología (STROBE): explicación y elaboración.

Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalisability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies and cross-sectional studies and four are specific to each of the three study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, one or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (http://www.strobe-statement.org/) should be helpful resources to improve reporting of observational research.

WITHDRAWN: Dieting to reduce body weight for controlling hypertension in adults.

BACKGROUND: As early as the 1920's, researchers noted a relationship between caloric restriction, weight loss and a decreased incidence of hypertension (Terry 1922, Preble 1923, Bauman 1928, Master 1929). In 1988 a meta-analysis of aggregate data from 12 prospective studies, including 5 randomized controlled trials (RCTs), found that on average each 1 kilogram decrease in body weight in obese hypertensive patients was associated with a 2.4 mm Hg systolic and 1.5 mm Hg diastolic decrease in blood pressure (Staessen 1988). Blood pressure reductions were not dependent upon degree of baseline obesity.This review aims to: 1) update the work of Staessen (Staessen 1988) looking specifically at randomized controlled trials, and 2) assess whether any of the trials assess effects of weight-reducing diets on clinical outcomes such as quality of life, morbidity or mortality. OBJECTIVES: Evaluate whether weight-loss diets are more effective than regular diets or other antihypertensive therapies in controlling blood pressure and preventing morbidity and mortality in hypertensive adults. SEARCH STRATEGY: MEDLINE and The Cochrane Library were searched through November 1997. Trials known to experts in the field were included through June 1998. SELECTION CRITERIA: For inclusion in the review, trials were required to meet each of the following criteria: 1) randomized controlled trials with one group assigned to a weight-loss diet and the other group assigned to either normal diet or antihypertensive therapy; 2) ambulatory adults with a mean blood pressure of at least 140 mm Hg systolic and/or 90 mm Hg diastolic; 3) active intervention consisting of a calorie-restricted diet intended to produce weight loss (excluded studies simultaneously implementing multiple lifestyle interventions where the effects of weight loss could not be disaggregated); and 4) outcome measures included weight loss and blood pressure. DATA COLLECTION AND ANALYSIS: Studies were dual abstracted by two independent reviewers using a standardized form designed specifically for this review. The primary mode of analysis was qualitative; graphs of effect sizes for individual studies were also used. MAIN RESULTS: Eighteen trials were found. Only one small study of inadequate power reported morbidity and mortality outcomes. None addressed quality of life or general well being issues. In general, participants assigned to weight-reduction groups lost weight compared to control groups.Six trials involving 361 participants assessed a weight-reducing diet versus a normal diet. The data suggested weight loss in the range of 4% to 8% of body weight was associated with a decrease in blood pressure in the range of 3 mm Hg systolic and diastolic. Three trials involving 363 participants assessed a weight-reducing diet versus treatment with antihypertensive medications. These suggested that a stepped-care approach with antihypertensive medications produced greater decreases in blood pressure (in the range of 6/5 mm Hg systolic/diastolic) than did a weight-loss diet. Trials that allowed adjustment of participants' antihypertensive regimens suggested that patients required less intensive antihypertensive drug therapy if they followed a weight-reducing diet. Data was insufficient to determine the relative efficacy of weight-reduction versus changes in sodium or potassium intake or exercise. AUTHORS' CONCLUSIONS: Weight-reducing diets in overweight hypertensive persons can affect modest weight loss in the range of 3-9% of body weight and are probably associated with modest blood pressure decreases of roughly 3 mm Hg systolic and diastolic. Weight-reducing diets may decrease dosage requirements of persons taking antihypertensive medications.

Strengthening the Reporting of Observational Studies in Epidemiology (STROBE): explanation and elaboration.

Much medical research is observational. The reporting of observational studies is often of insufficient quality. Poor reporting hampers the assessment of the strengths and weaknesses of a study and the generalizability of its results. Taking into account empirical evidence and theoretical considerations, a group of methodologists, researchers, and editors developed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) recommendations to improve the quality of reporting of observational studies. The STROBE Statement consists of a checklist of 22 items, which relate to the title, abstract, introduction, methods, results, and discussion sections of articles. Eighteen items are common to cohort studies, case-control studies, and cross-sectional studies, and 4 are specific to each of the 3 study designs. The STROBE Statement provides guidance to authors about how to improve the reporting of observational studies and facilitates critical appraisal and interpretation of studies by reviewers, journal editors, and readers. This explanatory and elaboration document is intended to enhance the use, understanding, and dissemination of the STROBE Statement. The meaning and rationale for each checklist item are presented. For each item, 1 or several published examples and, where possible, references to relevant empirical studies and methodological literature are provided. Examples of useful flow diagrams are also included. The STROBE Statement, this document, and the associated Web site (www.strobe-statement.org) should be helpful resources to improve reporting of observational research.