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PloS One 2012To review the effects of core stability exercise or general exercise for patients with chronic low back pain (LBP). (Meta-Analysis)
Meta-Analysis
OBJECTIVE
To review the effects of core stability exercise or general exercise for patients with chronic low back pain (LBP).
SUMMARY OF BACKGROUND DATA
Exercise therapy appears to be effective at decreasing pain and improving function for patients with chronic LBP in practice guidelines. Core stability exercise is becoming increasingly popular for LBP. However, it is currently unknown whether core stability exercise produces more beneficial effects than general exercise in patients with chronic LBP.
METHODS
Published articles from 1970 to October 2011 were identified using electronic searches. For this meta-analysis, two reviewers independently selected relevant randomized controlled trials (RCTs) investigating core stability exercise versus general exercise for the treatment of patients with chronic LBP. Data were extracted independently by the same two individuals who selected the studies.
RESULTS
From the 28 potentially relevant trials, a total of 5 trials involving 414 participants were included in the current analysis. The pooling revealed that core stability exercise was better than general exercise for reducing pain [mean difference (-1.29); 95% confidence interval (-2.47, -0.11); P = 0.003] and disability [mean difference (-7.14); 95% confidence interval (-11.64, -2.65); P = 0.002] at the time of the short-term follow-up. However, no significant differences were observed between core stability exercise and general exercise in reducing pain at 6 months [mean difference (-0.50); 95% confidence interval (-1.36, 0.36); P = 0.26] and 12 months [mean difference (-0.32); 95% confidence interval (-0.87, 0.23); P = 0.25].
CONCLUSIONS
Compared to general exercise, core stability exercise is more effective in decreasing pain and may improve physical function in patients with chronic LBP in the short term. However, no significant long-term differences in pain severity were observed between patients who engaged in core stability exercise versus those who engaged in general exercise.
SYSTEMATIC REVIEW REGISTRATION
http://www.crd.york.ac.uk/PROSPERO PROSPERO registration number: CRD42011001717.
Topics: Exercise Therapy; Humans; Low Back Pain; Publication Bias; Treatment Outcome
PubMed: 23284879
DOI: 10.1371/journal.pone.0052082 -
BMC Medical Research Methodology Jun 2020Publication and related biases (including publication bias, time-lag bias, outcome reporting bias and p-hacking) have been well documented in clinical research, but...
BACKGROUND
Publication and related biases (including publication bias, time-lag bias, outcome reporting bias and p-hacking) have been well documented in clinical research, but relatively little is known about their presence and extent in health services research (HSR). This paper aims to systematically review evidence concerning publication and related bias in quantitative HSR.
METHODS
Databases including MEDLINE, EMBASE, HMIC, CINAHL, Web of Science, Health Systems Evidence, Cochrane EPOC Review Group and several websites were searched to July 2018. Information was obtained from: (1) Methodological studies that set out to investigate publication and related biases in HSR; (2) Systematic reviews of HSR topics which examined such biases as part of the review process. Relevant information was extracted from included studies by one reviewer and checked by another. Studies were appraised according to commonly accepted scientific principles due to lack of suitable checklists. Data were synthesised narratively.
RESULTS
After screening 6155 citations, four methodological studies investigating publication bias in HSR and 184 systematic reviews of HSR topics (including three comparing published with unpublished evidence) were examined. Evidence suggestive of publication bias was reported in some of the methodological studies, but evidence presented was very weak, limited in both quality and scope. Reliable data on outcome reporting bias and p-hacking were scant. HSR systematic reviews in which published literature was compared with unpublished evidence found significant differences in the estimated intervention effects or association in some but not all cases.
CONCLUSIONS
Methodological research on publication and related biases in HSR is sparse. Evidence from available literature suggests that such biases may exist in HSR but their scale and impact are difficult to estimate for various reasons discussed in this paper.
SYSTEMATIC REVIEW REGISTRATION
PROSPERO 2016 CRD42016052333.
Topics: Bias; Health Services Research; Humans; Publication Bias; Research Design
PubMed: 32487022
DOI: 10.1186/s12874-020-01010-1 -
Journal of Medical Internet Research Jan 2022Metadata are created to describe the corresponding data in a detailed and unambiguous way and is used for various applications in different research areas, for example,... (Review)
Review
BACKGROUND
Metadata are created to describe the corresponding data in a detailed and unambiguous way and is used for various applications in different research areas, for example, data identification and classification. However, a clear definition of metadata is crucial for further use. Unfortunately, extensive experience with the processing and management of metadata has shown that the term "metadata" and its use is not always unambiguous.
OBJECTIVE
This study aimed to understand the definition of metadata and the challenges resulting from metadata reuse.
METHODS
A systematic literature search was performed in this study following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for reporting on systematic reviews. Five research questions were identified to streamline the review process, addressing metadata characteristics, metadata standards, use cases, and problems encountered. This review was preceded by a harmonization process to achieve a general understanding of the terms used.
RESULTS
The harmonization process resulted in a clear set of definitions for metadata processing focusing on data integration. The following literature review was conducted by 10 reviewers with different backgrounds and using the harmonized definitions. This study included 81 peer-reviewed papers from the last decade after applying various filtering steps to identify the most relevant papers. The 5 research questions could be answered, resulting in a broad overview of the standards, use cases, problems, and corresponding solutions for the application of metadata in different research areas.
CONCLUSIONS
Metadata can be a powerful tool for identifying, describing, and processing information, but its meaningful creation is costly and challenging. This review process uncovered many standards, use cases, problems, and solutions for dealing with metadata. The presented harmonized definitions and the new schema have the potential to improve the classification and generation of metadata by creating a shared understanding of metadata and its context.
Topics: Humans; Metadata; Publications; Reference Standards
PubMed: 35014967
DOI: 10.2196/25440 -
PloS One 2017A meta-analysis as part of a systematic review aims to provide a thorough, comprehensive and unbiased statistical summary of data from the literature. However, relevant... (Review)
Review
BACKGROUND
A meta-analysis as part of a systematic review aims to provide a thorough, comprehensive and unbiased statistical summary of data from the literature. However, relevant study results could be missing from a meta-analysis because of selective publication and inadequate dissemination. If missing outcome data differ systematically from published ones, a meta-analysis will be biased with an inaccurate assessment of the intervention effect. As part of the EU-funded OPEN project (www.open-project.eu) we conducted a systematic review that assessed whether the inclusion of data that were not published at all and/or published only in the grey literature influences pooled effect estimates in meta-analyses and leads to different interpretation.
METHODS AND FINDINGS
Systematic review of published literature (methodological research projects). Four bibliographic databases were searched up to February 2016 without restriction of publication year or language. Methodological research projects were considered eligible for inclusion if they reviewed a cohort of meta-analyses which (i) compared pooled effect estimates of meta-analyses of health care interventions according to publication status of data or (ii) examined whether the inclusion of unpublished or grey literature data impacts the result of a meta-analysis. Seven methodological research projects including 187 meta-analyses comparing pooled treatment effect estimates according to different publication status were identified. Two research projects showed that published data showed larger pooled treatment effects in favour of the intervention than unpublished or grey literature data (Ratio of ORs 1.15, 95% CI 1.04-1.28 and 1.34, 95% CI 1.09-1.66). In the remaining research projects pooled effect estimates and/or overall findings were not significantly changed by the inclusion of unpublished and/or grey literature data. The precision of the pooled estimate was increased with narrower 95% confidence interval.
CONCLUSIONS
Although we may anticipate that systematic reviews and meta-analyses not including unpublished or grey literature study results are likely to overestimate the treatment effects, current empirical research shows that this is only the case in a minority of reviews. Therefore, currently, a meta-analyst should particularly consider time, effort and costs when adding such data to their analysis. Future research is needed to identify which reviews may benefit most from including unpublished or grey data.
Topics: Humans; Information Dissemination; Meta-Analysis as Topic; Publication Bias; Publications
PubMed: 28441452
DOI: 10.1371/journal.pone.0176210 -
Annals of the Royal College of Surgeons... Jul 2018Introduction Surgeon-specific outcome data, or consultant outcome publication, refers to public access to named surgeon procedural outcomes. Consultant outcome... (Review)
Review
Introduction Surgeon-specific outcome data, or consultant outcome publication, refers to public access to named surgeon procedural outcomes. Consultant outcome publication originates from cardiothoracic surgery, having been introduced to US and UK surgery in 1991 and 2005, respectively. It has been associated with an improvement in patient outcomes. However, there is concern that it may also have led to changes in surgeon behaviour. This review assesses the literature for evidence of risk-averse behaviour, upgrading of patient risk factors and cessation of low-volume or poorly performing surgeons. Materials and methods A systematic literature review of Embase and Medline databases was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Original studies including data on consultant outcome publication and its potential effect on surgeon behaviour were included. Results Twenty-five studies were identified from the literature search. Studies suggesting the presence of risk-averse behaviour and upgrading of risk factors tended to be survey based, with studies contrary to these findings using recognised regional and national databases. Discussion and conclusion Our review includes instances of consultant outcome publication leading to risk-averse behaviour, upgrading of risk factors and cessation of low-volume or poorly performing surgeons. As UK data on consultant outcome publication matures, further research is essential to ensure that high-risk patients are not inappropriately turned down for surgery.
Topics: Humans; Outcome Assessment, Health Care; Patient Selection; Practice Patterns, Physicians'; Publishing; Quality Improvement; Risk Assessment; Risk-Taking; Surgeons; United Kingdom; United States
PubMed: 29962298
DOI: 10.1308/rcsann.2018.0052 -
PloS One Aug 2008The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a... (Review)
Review
BACKGROUND
The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias has been recognised as a potential threat to the validity of meta-analysis and can make the readily available evidence unreliable for decision making. Until recently, outcome reporting bias has received less attention.
METHODOLOGY/PRINCIPAL FINDINGS
We review and summarise the evidence from a series of cohort studies that have assessed study publication bias and outcome reporting bias in randomised controlled trials. Sixteen studies were eligible of which only two followed the cohort all the way through from protocol approval to information regarding publication of outcomes. Eleven of the studies investigated study publication bias and five investigated outcome reporting bias. Three studies have found that statistically significant outcomes had a higher odds of being fully reported compared to non-significant outcomes (range of odds ratios: 2.2 to 4.7). In comparing trial publications to protocols, we found that 40-62% of studies had at least one primary outcome that was changed, introduced, or omitted. We decided not to undertake meta-analysis due to the differences between studies.
CONCLUSIONS
Recent work provides direct empirical evidence for the existence of study publication bias and outcome reporting bias. There is strong evidence of an association between significant results and publication; studies that report positive or significant results are more likely to be published and outcomes that are statistically significant have higher odds of being fully reported. Publications have been found to be inconsistent with their protocols. Researchers need to be aware of the problems of both types of bias and efforts should be concentrated on improving the reporting of trials.
Topics: Clinical Trials as Topic; Cohort Studies; Humans; Patient Selection; Publication Bias; Publishing; Randomized Controlled Trials as Topic; Treatment Outcome
PubMed: 18769481
DOI: 10.1371/journal.pone.0003081 -
PloS One 2013The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The increased use of meta-analysis in systematic reviews of healthcare interventions has highlighted several types of bias that can arise during the completion of a randomised controlled trial. Study publication bias and outcome reporting bias have been recognised as a potential threat to the validity of meta-analysis and can make the readily available evidence unreliable for decision making.
METHODOLOGY/PRINCIPAL FINDINGS
In this update, we review and summarise the evidence from cohort studies that have assessed study publication bias or outcome reporting bias in randomised controlled trials. Twenty studies were eligible of which four were newly identified in this update. Only two followed the cohort all the way through from protocol approval to information regarding publication of outcomes. Fifteen of the studies investigated study publication bias and five investigated outcome reporting bias. Three studies have found that statistically significant outcomes had a higher odds of being fully reported compared to non-significant outcomes (range of odds ratios: 2.2 to 4.7). In comparing trial publications to protocols, we found that 40-62% of studies had at least one primary outcome that was changed, introduced, or omitted. We decided not to undertake meta-analysis due to the differences between studies.
CONCLUSIONS
This update does not change the conclusions of the review in which 16 studies were included. Direct empirical evidence for the existence of study publication bias and outcome reporting bias is shown. There is strong evidence of an association between significant results and publication; studies that report positive or significant results are more likely to be published and outcomes that are statistically significant have higher odds of being fully reported. Publications have been found to be inconsistent with their protocols. Researchers need to be aware of the problems of both types of bias and efforts should be concentrated on improving the reporting of trials.
Topics: Cohort Studies; Humans; Outcome Assessment, Health Care; Publication Bias; Publications; Randomized Controlled Trials as Topic
PubMed: 23861749
DOI: 10.1371/journal.pone.0066844 -
BMC Cancer Mar 2018Systematic reviews, with or without meta-analysis, play an important role today in synthesizing cancer research and are frequently used to guide decision-making.... (Review)
Review
Systematic reviews, with or without meta-analysis, play an important role today in synthesizing cancer research and are frequently used to guide decision-making. However, there is now an increase in the number of systematic reviews on the same topic, thereby necessitating a systematic review of previous systematic reviews. With a focus on cancer, the purpose of this article is to provide a practical, stepwise approach for systematically reviewing the literature and publishing the results. This starts with the registration of a protocol for a systematic review of previous systematic reviews and ends with the publication of an original or updated systematic review, with or without meta-analysis, in a peer-reviewed journal. Future directions as well as potential limitations of the approach are also discussed. It is hoped that the stepwise approach presented in this article will be helpful to both producers and consumers of cancer-related systematic reviews and will contribute to the ultimate goal of preventing and treating cancer.
Topics: Biomedical Research; Evidence-Based Medicine; Humans; Meta-Analysis as Topic; Neoplasms; Peer Review, Research; Research Design
PubMed: 29499652
DOI: 10.1186/s12885-018-4163-6 -
Health Technology Assessment... Oct 2008To identify the expected delay between publication of conference abstracts and full publication of results from trials of new anti-cancer agents for breast cancer and to... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVES
To identify the expected delay between publication of conference abstracts and full publication of results from trials of new anti-cancer agents for breast cancer and to identify whether there are any apparent biases in publication and reporting.
DATA SOURCES
Major electronic databases were searched to identify randomised controlled trials (RCTs) of the selected interventions for the treatment of breast cancer.
REVIEW METHODS
A systematic review was conducted according to standard methods. Data were extracted from the included studies using a predesigned and piloted data extraction template.
RESULTS
Six anti-cancer treatments for breast cancer were included in the review: docetaxel, paclitaxel, trastuzumab, gemcitabine, lapatinib and bevacizumab. The literature searches generated 1556 references, from which 71 publications were retrieved and screened for inclusion. Screening identified 41 publications of 18 RCTs with at least one arm of treatment meeting the inclusion criteria for the review. Of the 18 included RCTs, only four publications (from three RCTs) reported the same outcomes in both an abstract and a full publication. Time between the abstract and full publication was 5 months in two cases, 7 months in one case and 19 months in one case (overall mean delay = 9 months). Eleven trials were identified that have not currently published in a full publication the data presented in an abstract or conference proceeding. The duration between publication of the abstracts and the end of August 2007 varied from 3 months to 38 months (mean delay 16.5 months). The longest delays in publication were for trials investigating gemcitabine (38 months) or bevacizumab (33 months). Observational analysis of the published and unpublished trials did not indicate any particular biases in terms of whether positive results were more likely to be fully published than non-significant ones.
CONCLUSIONS
It was surprising that only three of the 18 relevant RCTs had one or more full papers that reported the same outcome measures (and stage of analysis) as an earlier conference abstract. However, a limitation of this review is the small number of studies included. With a larger sample size than that in the present report, investigation into the effect of publication delay on decision-making might be feasible. Future research should include extension of this work to other anti-cancer drugs and investigation into the reasons for lengthy delays to full publication noted for some trials.
Topics: Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Bevacizumab; Breast Neoplasms; Consensus Development Conferences as Topic; Databases, Bibliographic; Deoxycytidine; Docetaxel; Female; Humans; Lapatinib; Paclitaxel; Publication Bias; Publishing; Quinazolines; Randomized Controlled Trials as Topic; Taxoids; Technology Assessment, Biomedical; Time; Trastuzumab; Gemcitabine
PubMed: 18831948
DOI: 10.3310/hta12320 -
Medicine Mar 2018The utilization and impact of the studies published using the National Cancer Database (NCDB) is currently unclear. In this study, we aim to characterize the published... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
The utilization and impact of the studies published using the National Cancer Database (NCDB) is currently unclear. In this study, we aim to characterize the published studies, and identify relatively unexplored areas for future investigations.
METHODS
A literature search was performed using PubMed in January 2017 to identify all papers published using NCDB data. Characteristics of the publications were extracted. Citation frequencies were obtained through the Web of Science.
RESULTS
Three hundred 2 articles written by 230 first authors met the inclusion criteria. The number of publications grew exponentially since 2013, with 108 articles published in 2016. Articles were published in 86 journals. The majority of the published papers focused on digestive system cancer, while bone and joints, eye and orbit, myeloma, mesothelioma, and Kaposi Sarcoma were never studied. Thirteen institutions in the United States were associated with more than 5 publications. The papers have been cited for a total of 9858 times since the publication of the first paper in 1992. Frequently appearing keywords congregated into 3 clusters: "demographics," "treatments and survival," and "statistical analysis method." Even though the main focuses of the articles captured a extremely wide range, they can be classified into 2 main categories: survival analysis and characterization. Other focuses include database(s) analysis and/or comparison, and hospital reporting.
CONCLUSION
The surging interest in the use of NCDB is accompanied by unequal utilization of resources by individuals and institutions. Certain areas were relatively understudied and should be further explored.
Topics: Databases, Factual; Health Resources; Humans; Journal Impact Factor; Neoplasms; Publications; United States
PubMed: 29489679
DOI: 10.1097/MD.0000000000009823