Well-conducted Systematic Reviews Research Articles

Consumption of ultra-processed foods and multiple health outcomes: An umbrella study of meta-analyses

Consumption of ultra-processed foods (UPFs) is associated with various adverse health outcomes, which significantly influence the global disease burden. This umbrella review aimed to fill the knowledge gap and guide public health practices by summarizing the association between UPFs and multiple health outcomes. A total of four databases were systematically searched from inception to December 2022, and 14 eligible systematic reviews (SRs) with meta-analyses (MAs) were identified. The SRs were published in 10 journals from 2020 to 2023, with 54,147–5,750,133 participants and 5–61 studies. The overall corrected covered area (CCA) was corresponded to a slight overlap. The results showed that an increased UPFs consumption is associated with multiple health outcomes (e.g., obesity, diabetes, hypertension, mortality). Only two SRs were “Moderate” regarding the overall methodological quality, while the other twelve were “Low” or “Critically low”. Therefore, well-conducted SRs with high-quality prospective cohorts with a particular focus on special populations are needed to verify these findings further.

WITHDRAWN: Evidence Synthesis to Advance Clinical Practice and Scientific Research: A CGH Pillar

WITHDRAWN: Evidence Synthesis to Advance Clinical Practice and Scientific Research: A CGH Pillar

Lack of sex-related analysis and reporting in Cochrane Reviews: a cross-sectional study

BackgroundSex-specific analysis and reporting may allow a better understanding of intervention effects and can support the decision-making process. Well-conducted systematic reviews (SRs), like those carried out by the Cochrane Collaboration, provide clinical responses transparently and stress gaps of knowledge. This study aimed to describe the extent to which sex is analysed and reported in a cross-section of Cochrane SRs of interventions, and assess the association with the gender of main authorships.MethodsWe searched SRs published during 2018 within the Cochrane Database of Systematic Reviews. An investigator appraised the sex-related analysis and reporting across sections of SRs and collected data on gender and country of affiliation of the review first and last authors, and a second checked for accuracy. We conducted descriptive statistics and bivariate logistic regression to explore the association between the gender of the authors and sex-related analysis and reporting.ResultsSix hundred and ten Cochrane SRs were identified. After removing those that met no eligibility criteria, 516 reviews of interventions were included. Fifty-six reviews included sex-related reporting in the abstract, 90 considered sex in their design, 380 provided sex-disaggregated descriptive data, 142 reported main outcomes or performed subgroup analyses by sex, and 76 discussed the potential impact of sex or the lack of such on the interpretations of findings. Women represented 53.1 and 42.2% of first and last authorships, respectively. Women authors (in first and last position) had a higher possibility to report sex in at least one of the review sections (OR 2.05; CI 95% 1.12–3.75, P=0.020) than having none.ConclusionsSex consideration amongst Cochrane SRs was frequently missing. Structured guidance to sex-related analysis and reporting is needed to enhance the external validity of findings. Likewise, including gender diversity within the research workforce and relevant authorship positions may foster equity in the evidence generated.

Reliability of the evidence to guide decision-making in foot ulcer prevention in diabetes: an overview of systematic reviews

BackgroundReliable evidence on the effectiveness of interventions to prevent diabetes-related foot ulceration is essential to inform clinical practice. Well-conducted systematic reviews that synthesise evidence from all relevant trials offer the most robust evidence for decision-making. We conducted an overview to assess the comprehensiveness and utility of the available secondary evidence as a reliable source of robust estimates of effect with the aim of informing a cost-effective care pathway using an economic model. Here we report the details of the overview. [PROSPERO Database (CRD42016052324)].MethodsMedline (Ovid), Embase (Ovid), Epistomonikos, Cochrane Database of Systematic Reviews (CDSR), Database of s of Reviews of Effectiveness (DARE), and the Health Technology Assessment Journals Library were searched to 17th May 2021, without restrictions, for systematic reviews of randomised controlled trials (RCTs) of preventive interventions in people with diabetes. The primary outcomes of interest were new primary or recurrent foot ulcers. Two reviewers independently extracted data and assessed the risk of bias in the included reviews.FindingsThe overview identified 30 systematic reviews of patient education, footwear and off-loading, complex and other interventions. Many are poorly reported and have fundamental methodological shortcomings associated with increased risk of bias. Most concerns relate to vague inclusion criteria (60%), weak search or selection strategies (70%) and quality appraisal methods (53%) and inexpert conduct and interpretation of quantitative and narrative evidence syntheses (57%). The 30 reviews have collectively assessed 26 largely poor-quality RCTs with substantial overlap.InterpretationThe majority of these systematic reviews of the effectiveness of interventions to prevent diabetic foot ulceration are at high risk of bias and fail to provide reliable evidence for decision-making. Adherence to the core principles of conducting and reporting systematic reviews is needed to improve the reliability of the evidence generated to inform clinical practice.

Efficacy and safety of osteopathic manipulative treatment: an overview of systematic reviews

ObjectiveTo summarise the available clinical evidence on the efficacy and safety of osteopathic manipulative treatment (OMT) for different conditions.DesignOverview of systematic reviews (SRs) and meta-analyses (MAs). PROSPERO CRD42020170983.Data sourcesAn electronic...

Low methodological quality of systematic reviews on acupuncture: a cross-sectional study

BackgroundWhile well-conducted systematic reviews (SRs) can provide the best evidence on the potential effectiveness of acupuncture, limitations on the methodological rigour of SRs may impact the trustworthiness of their conclusions. This cross-sectional study aimed to evaluate the methodological quality of a representative sample of SRs on acupuncture effectiveness.MethodsCochrane Database of Systematic Reviews, MEDLINE, and EMBASE were searched for SRs focusing on the treatment effect of manual acupuncture or electro-acupuncture published during January 2018 and March 2020. Eligible SRs must contain at least one meta-analysis and be published in English language. Two independent reviewers extracted the bibliographical characteristics of the included SRs with a pre-designed questionnaire and appraised the methodological quality of the studies with the validated AMSTAR 2 (A MeaSurement Tool to Assess systematic Reviews 2). The associations between bibliographical characteristics and methodological quality ratings were explored using Kruskal-Wallis rank tests and Spearman’s rank correlation coefficients.ResultsA total of 106 SRs were appraised. Only one (0.9%) SR was of high overall methodological quality, zero (0%) was of moderate-quality, six (5.7%) and 99 (93.4%) were of low-quality and critically low-quality respectively. Among appraised SRs, only ten (9.4%) provided an a priori protocol, four (3.8%) conducted a comprehensive literature search, five (4.7%) provided a list of excluded studies, and six (5.7%) performed meta-analysis appropriately. Cochrane SRs, updated SRs, and SRs that did not search non-English databases had relatively higher overall quality.ConclusionsMethodological quality of SRs on acupuncture is unsatisfactory. Future reviewers should improve critical methodological aspects of publishing protocols, performing comprehensive search, providing a list of excluded studies with justifications for exclusion, and conducting appropriate meta-analyses. These recommendations can be implemented via enhancing the technical competency of reviewers in SR methodology through established education approaches as well as quality gatekeeping by journal editors and reviewers. Finally, for evidence users, skills in SR critical appraisal remain to be essential as relevant evidence may not be available in pre-appraised formats.

Tai Chi for Chronic Obstructive Pulmonary Disease (COPD): An Overview of Systematic Reviews.

ObjectiveSince current systematic reviews (SRs) show that results of effectiveness on Tai Chi for chronic obstructive pulmonary disease (COPD) are inconsistent, the purpose of this study is to find the reasons of the disparity by comprehensively appraising the related SRs.MethodsSix databases were systematically searched from the inception date to April 17, 2021. The methodological quality, the risk of bias, the reporting quality, and the quality of evidence were independently assessed by two reviewers with the AMSTAR 2, ROBIS, PRISMA, and GRADE.ResultsA total of 12 studies met the inclusion criteria: 10 SRs were rated critically low quality and two SRs were low quality by AMSTAR 2. By the ROBIS, four out of 12 SRs were rated as “low risk”. According to PRISMA, nine out of 12 SRs were adequately reported over 80%. With the GRADE tool, three out of 12 SRs rated the FEV1 as “Moderate”, one out of 12 SRs (1/12, 9%) rated the FEV1/FVC (%) as “Moderate”, three out of 12 SRs assessed the 6MWD as “Moderate”, three out of 12 SRs evaluated the SGRQ as “Moderate”, and the remaining evidence was fully rated as “Low” or “Very Low”.ConclusionWe found that the methodological quality, risk of bias, reporting quality, and quality of evidence of the included SRs on Tai Chi for COPD were suboptimal. These limitations may have a negative impact on SRs, consequently leading to inconsistent results. Further well-conducted SRs with less risk of bias, more rigorous methodology, normative reporting and high-quality of evidence are needed to provide robust evidence on Tai Chi for COPD.Registration NumberThis study has been registered in the PROSPERO International Prospective Register of Systematic Reviews (registration number: CRD42019126600).

Practice-Based Research in Complementary Medicine: Could N-of-1 Trials Become the New Gold Standard?

Complementary medicines and therapies are popular forms of healthcare with a long history of traditional use. Yet, despite increasing consumer demand, there is an ongoing exclusion of complementary medicines from mainstream healthcare systems. A lack of evidence is often cited as justification. Until recently, high-quality evidence of treatment efficacy was defined as findings from well-conducted systematic reviews and meta-analyses of randomized controlled trials. In a recent and welcome move by the Oxford Centre for Evidence-Based Practice, however, the N-of-1 trial design has also been elevated to the highest level of evidence for treatment efficacy of an individual, placing this research design on par with the meta-analysis. N-of-1 trial designs are experimental research methods that can be implemented in clinical practice. They incorporate much of the rigor of group clinical trials, but are designed for individual patients. Individualizing treatment interventions and outcomes in research designs is consistent with the movement towards patient-centered care and aligns well with the principles of holism as practiced by naturopaths and many other complementary medicine practitioners. This paper explores whether rigorously designed and conducted N-of-1 trials could become a new ‘gold standard’ for demonstrating treatment efficacy for complementary medicine interventions in individual patients in clinical practice.

Lack of evidence on mental health and well-being impacts of individual-level interventions for vulnerable adolescents: systematic mapping review.

ObjectivesTo review empirical evaluations of individual-level interventions intended to improve mental health or well-being for vulnerable adolescents.Study designThis is a systematic mapping review.MethodsThirteen databases covering academic and gray literature were searched for published reviews and randomised controlled trials, and gray literature (2005–2016) and the results quality-assessed to prioritise best available evidence. We aimed to identify well-conducted systematic reviews and trials that evaluated individual-level interventions, for mental health/well-being outcomes, where the population was adolescents aged 10–24 years in any of 12 vulnerable groups at high risk of poor health outcomes (e.g. homeless, offenders, ‘looked after’, carers).ResultsThirty systematic reviews and 16 additional trials were identified. There was insufficient evidence to identify promising individual-level interventions that improve the mental health/well-being of any of the vulnerable groups.ConclusionsDespite Western policy to promote health and well-being among vulnerable young people, the dearth of evidence suggests a lack of interest in evaluating interventions targeting these groups in respect of their mental health/well-being outcomes.

The Quality of Systematic Reviews in Head and Neck Microsurgery: A Perspective from Plastic Surgery and Otolaryngology.

In recent years, there has been a push to publish higher level of evidence studies in medicine, particularly in plastic surgery. Well-conducted systematic reviews are considered the strongest level of evidence in medicine, recently becoming the key process indicators for quality delivery. A varying quality of systematic reviews, however, has led to concerns of their validity in clinical decision-making. We perform a quality analysis of systematic reviews published in head and neck microsurgery by the surgical specialties of plastic surgery and otolaryngology. An evaluation of systematic reviews published on microsurgery in 13 high-impact surgical journals was conducted by searching PubMed and Scopus. Two authors independently performed searches, screened for eligibility, and extracted data from included articles. Discrepancies were resolved by discussion and consensus. Assessment of Multiple Systematic Reviews (AMSTAR) criteria were used to assess methodological quality. The initial database search retrieved 166 articles. After removing duplicates, screening titles and abstracts, 26 articles remained for full text review. Seven did not focus on head and neck microsurgery and were further excluded, leaving 19 systematic reviews for final analysis. Of those, 10 systematic reviews were published by otolaryngology, and 9 were published by plastic surgery. Median AMSTAR score was 8 for otolaryngology, 7 for plastic surgery, and 8 overall, reflecting "fair to good" quality. The number of systematic reviews on head and neck microsurgery markedly increased over time. Of note, both the AMSTAR score and the number of systematic reviews published by plastic surgery have steadily increased from 2014 to 2016, whereas those published by otolaryngology have remained relatively stable since 2010. Our review shows a trend toward publishing more systematic reviews. The increasing quantity and quality of systematic reviews published by plastic surgeons indicates recognition in the need for higher levels of evidence in plastic surgery, as well as growing interest and advances in microsurgery. Given these trends, familiarity with quality assessment guidelines, such as AMSTAR, will remain important in providing a basis for building relevant value-based quality measures.

Synthesizing and Appraising the Quality of the Evidence on Factors Associated with Medication Adherence in Diabetes: A Systematic Review of Systematic Reviews

BackgroundNonadherence to medications is a common phenomenon in patients with diabetes. Several studies and systematic reviews have investigated the barriers to medication adherence in diabetes. However, no study has evaluated the quality of the existing literature and synthesized the plethora of evidence with a goal to design holistic conceptual frameworks and interventions. ObjectivesThe aims of this review were to systematically evaluate existing systematic reviews focusing on factors associated with medication adherence in diabetes in an effort to synthesize the evidence, determine their methodological quality, and identify the gaps in the current literature. MethodsFourteen databases and gray literature sources were systematically searched through June 2016. Systematic reviews reporting factors associated with medication adherence (barriers and facilitators) in patients with diabetes were selected on the basis of predetermined criteria. Studies were appraised for quality using AMSTAR (A Measurement Tool to Assess Systematic Reviews). ResultsSeventeen systematic reviews including 542 primary studies, most of which were cross-sectional quantitative studies, were included. All the reviews were rated as moderate to low quality and exhibited common methodological pitfalls. Factors influencing medication adherence identified were categorized as patient-, medication-, disease-, health care provider–, health care system–, and social-related factors. ConclusionsFactors influencing medication adherence are multifactorial with remarkably consistent findings across the existing reviews; yet, most reviews were judged to be of low to moderate quality. Further comprehensive and well-conducted original studies and systematic reviews on this topic shall be conducted taking into consideration the drawbacks of existing ones.

Prophylactic Extraction of Third Molars: Evidence-Based Dentistry

This new perspective article was performed to investigate the evidence from published dental literature about the prophylactic extraction of asymptomatic (or disease-free) impacted third molars (ITM) in adolescents and young adults. This clinical procedure is common until today and has been the origin of controversy among the dental community worldwide. However, evidence-based data from well-conducted clinical studies and systematic reviews are not sufficient to justify the routine prophylactic extraction of ITM. Active surveillance at regular intervals has been proposed as a better management strategy. As a conclusion, surgical removal of ITM is only justified in the presence of specific pathosis, independently of the patient’s age.

Prophylactic Extraction of Third Molars: Evidence-Based Dentistry

This new perspective article was performed to investigate the evidence from published dental literature about the prophylactic extraction of asymptomatic (or disease-free) impacted third molars (ITM) in adolescents and young adults. This clinical procedure is common until today and has been the origin of controversy among the dental community worldwide. However, evidence-based data from well-conducted clinical studies and systematic reviews are not sufficient to justify the routine prophylactic extraction of ITM. Active surveillance at regular intervals has been proposed as a better management strategy. As a conclusion, surgical removal of ITM is only justified in the presence of specific pathosis, independently of the patient’s age.

Methodological quality of systematic reviews on treatments for depression: a cross-sectional study.

Depression is one of the most common mental disorders and identifying effective treatment strategies is crucial for the control of depression. Well-conducted systematic reviews (SRs) and meta-analyses can provide the best evidence for supporting treatment decision-making. Nevertheless, the trustworthiness of conclusions can be limited by lack of methodological rigour. This study aims to assess the methodological quality of a representative sample of SRs on depression treatments. A cross-sectional study on the bibliographical and methodological characteristics of SRs published on depression treatments trials was conducted. Two electronic databases (the Cochrane Database of Systematic Reviews and the Database of Abstracts of Reviews of Effects) were searched for potential SRs. SRs with at least one meta-analysis on the effects of depression treatments were considered eligible. The methodological quality of included SRs was assessed using the validated AMSTAR (Assessing the Methodological Quality of Systematic Reviews) tool. The associations between bibliographical characteristics and scoring on AMSTAR items were analysed using logistic regression analysis. A total of 358 SRs were included and appraised. Over half of included SRs (n = 195) focused on non-pharmacological treatments and harms were reported in 45.5% (n = 163) of all studies. Studies varied in methods and reporting practices: only 112 (31.3%) took the risk of bias among primary studies into account when formulating conclusions; 245 (68.4%) did not fully declare conflict of interests; 93 (26.0%) reported an 'a priori' design and 104 (29.1%) provided lists of both included and excluded studies. Results from regression analyses showed: more recent publications were more likely to report 'a priori' designs [adjusted odds ratio (AOR) 1.31, 95% confidence interval (CI) 1.09-1.57], to describe study characteristics fully (AOR 1.16, 95% CI 1.06-1.28), and to assess presence of publication bias (AOR 1.13, 95% CI 1.06-1.19), but were less likely to list both included and excluded studies (AOR 0.86, 95% CI 0.81-0.92). SRs published in journals with higher impact factor (AOR 1.14, 95% CI 1.04-1.25), completed by more review authors (AOR 1.12, 95% CI 1.01-1.24) and SRs on non-pharmacological treatments (AOR 1.62, 95% CI 1.01-2.59) were associated with better performance in publication bias assessment. The methodological quality of included SRs is disappointing. Future SRs should strive to improve rigour by considering of risk of bias when formulating conclusions, reporting conflict of interests and authors should explicitly describe harms. SR authors should also use appropriate methods to combine the results, prevent language and publication biases, and ensure timely updates.

Methodologic Quality of Systematic Reviews Published in the Plastic and Reconstructive Surgery Literature

Well-conducted systematic reviews have a critical role in informing evidence-based decision-making in plastic surgery. The authors' objective was to assess the methodologic quality of systematic reviews in the plastic surgery literature. The authors systematically assessed all systematic reviews in 10 high-impact plastic surgery journals using MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials, and the Cochrane Database of Systematic Reviews from 2003 to 2013. These were evaluated for methodologic quality using A Measurement Tool to Assess Systematic Reviews (AMSTAR), a validated 11-point instrument. After removal of duplicates and screening titles and abstracts, 190 systematic reviews met eligibility criteria. The majority of systematic reviews were published in Plastic and Reconstructive Surgery (n = 88). The most common domain covered was reconstruction (17.9 percent). Using AMSTAR, the median score was 4 (interquartile range, 2.25 to 6.00) on a scale of 1 to 11. No increase in AMSTAR score was observed with time (p = 0.18). Almost half of all systematic reviews (48.4 percent) included at least two independent data extractors, and less than one-third of them (15.3 percent) searched unpublished studies or provided a list of both included and excluded studies (14.8 percent). The methodologic quality of included primary studies was evaluated in 35.3 percent. Systematic reviews in plastic surgery demonstrated inadequate adherence to methodologic standards of quality, which raises concerns about validity. There has been an increase in the number of systematic reviews published in plastic surgery over the past decade, yet there has been no significant improvement observed in methodologic quality.

Methodological challenges when performing a systematic review.

Well-conducted systematic reviews can provide a foundation upon which to base educational curricula, practice guidelines and healthcare policy. We aim to provide an overview of important methodological issues that need to be addressed during the five phases of performing a systematic review. 1. The specific problems to be addressed by the systematic review need to be formulated as clear, unambiguous and structured question/s. 2. Literature from multiple resources should be searched to avoid publication biases, as positive outcomes are more likely to be published than null/negative results. 3. The quality of selected articles should be assessed using a checklist, while the reliability of graders, as well as the quality of the checklist, needs to be established a priori. 4. Statistical heterogeneity needs to be assessed to determine if a meta-analysis is appropriate to pool the data. If not, a narrative synthesis of the evidence/overall findings needs to be performed within a clinical context.

How much do we know about schizophrenia and how well do we know it? Evidence from the Schizophrenia Library.

True findings about schizophrenia remain elusive; many findings are not replicated and conflicting results are common. Well-conducted systematic reviews have the ability to make robust, generalizable conclusions, with good meta-analyses potentially providing the closest estimate of the true effect size. In this paper, we undertake a systematic approach to synthesising the available evidence from well-conducted systematic reviews on schizophrenia. Reviews were identified by searching Medline, EMBASE, CINAHL, Current Contents and PsycINFO. The decision to include or exclude reviews, data extraction and quality assessments were conducted in duplicate. Evidence was graded as high quality if reviews contained large samples and robust results; and as moderate quality if reviews contained imprecision, inconsistency, smaller samples or study designs that may be prone to bias. High- and moderate-quality evidence shows that numerous psychosocial and biomedical treatments are effective. Patients have relatively poor cognitive functioning, and subtle, but diverse, structural brain alterations, altered electrophysiological functioning and sleep patterns, minor physical anomalies, neurological soft signs, and sensory alterations. There are markers of infection, inflammation or altered immunological parameters; and there is increased mortality from a range of causes. Risk for schizophrenia is increased with cannabis use, pregnancy and birth complications, prenatal exposure to Toxoplasma gondii, childhood central nervous system viral infections, childhood adversities, urbanicity and immigration (first and second generation), particularly in certain ethnic groups. Developmental motor delays and lower intelligence quotient in childhood and adolescence are apparent. We conclude that while our knowledge of schizophrenia is very substantial, our understanding of it remains limited.

Understanding systematic reviews and meta-analyses

Systematic reviews and meta-analyses of randomised controlled trials are increasingly being used by healthcare professionals, policy makers, budget holders and patients to inform decisions relating to the effectiveness of competing...

Editorial: How Much Do PPIs Contribute to C. difficile Infections?

Two separate systematic reviews and meta-analyses published in this edition of the American Journal of Gastroenterology conclude that proton pump inhibitor (PPI) use is associated with an ~70% increase in the risk of Clostridium difficile infection (CDI). The two reviews employed different methodology but reached very similar conclusions. However, since the quality of evidence from the individual studies that were included in these analyses is relatively weak, their conclusions must be interpreted cautiously. Observational studies--and even well-conducted systematic reviews of observational studies--rarely provide adequate evidence to prove causality rather than mere association. However, given both the widespread use of PPIs and the increasing incidence and importance of CDI, it is important that this association is adequately explored.

Effectiveness of interventions to promote healthy weight in general populations of children and adults: a meta-analysis

Responding to the obesity epidemic requires robust evidence to help prioritize the allocation of scarce resources to preventive interventions. The aim of this study was to evaluate interventions that promote healthy weight [defined as reduction in body mass index (BMI) or percentage body fat] in general populations (unselected by weight) using a comprehensive meta-analysis. Interventions with both single and multiple components were considered. Studies were first identified through well-conducted systematic reviews complemented by a search for single studies in five large medical databases up to 6 November 2008. Sixty-eight controlled studies were included. For each intervention type and age group, all relevant studies were pooled in a random effects meta-analysis. In children, the highest reductions in mean BMI were achieved through promoting reduced television viewing [-0.27 kg/m(2) (95% CI -0.4 to -0.13 kg/m(2))]. Programmes combining physical activity, specifically themed or general health education and nutrition achieved a lower reduction [-0.1 kg/m(2) (95% CI -0.17 to -0.04 kg/m(2))]. Other interventions had high heterogeneity or showed no statistically significant reduction in outcomes. In adults, single component interventions were found to reduce both outcome measures. Their mean percentage body fat was reduced through education by -1.22% (95% CI -1.92 to -0.52). The evidence for the effectiveness of promoting healthy weight in general populations is limited, though multi-component interventions in schools and encouraging reduced children's television viewing are promising strategies. Improving the reporting of outcomes is vital, as imputation of inadequately reported measures may have contributed to the observed heterogeneity. Longer follow-up is essential for understanding policy relevance.