Financial conflicts of interest in systematic reviews: associations with results, conclusions, and methodological quality

Industry effects on evidence: a case study of long-acting injectable antipsychotics

A vigorously debated issue in the psychiatric literature is whether long-acting injectable antipsychotics (LAIs) show clinical benefit over antipsychotics taken orally. In addressing this question, it is critical that systematic reviews incorporate risk of bias assessments of trial data in a robust way and are free of undue industry influence. In this paper, we present a case analysis in which we identify some of the design problems in a recent systematic review on LAIs vs oral formulations. This case illustrates how evidence syntheses that are shaped by commercial interests may undermine patient-centered models of recovery and care. We offer recommendations that address both the bioethical and research design issues that arise in the systematic review process when researchers have financial conflicts of interest.

Management of evidence and conflict of interest in guidelines on early childhood allergy prevention and child nutrition: study protocol of a systematic synthesis of guidelines and explorative network analysis

Background

With the rising prevalence of allergic diseases in children, prevention of childhood allergies becomes an important public health issue. Recently, a paradigm shift is taking place in the approach to preventing allergies, and clinical practice guidelines (CPG) and food-based dietary guidelines (FBDG) play an important role in providing practitioners with the latest evidence and reliable guidance. However, concern about the methodological quality of the development of FBDGs and CPGs, including limitations in the systematic reviews, lack of transparency and unmanaged conflicts of interest (COI), reduce the trust in these guidelines.

Methods

We aim to synthesize the available guidance on early childhood allergy prevention (ECAP) through a systematic search for national and international CPGs and FBDGs concerning ECAP and child nutrition (CN) and to assess the quality of the guidelines and management of COI. Additionally, we will analyse the content and the evidence base of the recommendation statements. We aim to quantify the COI in guideline panellists and explore possible associations between COI and recommendations. Through a social network analysis, we expect to elucidate ties between panellists, researchers, institutions, industry and other sponsors. Guidelines are an important tool to inform healthcare practitioners with the newest evidence, but quality and reliability have to be high. This study will help identify potential for further improvement in the development of guidelines and the management of COI. If the social network analysis proves feasible and reveals more information on COI in comparison to disclosed COI from the previous analyses, the methodology can be developed further to identify undisclosed COIs in panelists.

Ethics and dissemination

This research does not require ethical approval because no human subjects are involved. Results will be published in international peer-reviewed open access journals and via presentations at scientific conferences.

Appraising systematic reviews: a comprehensive guide to ensuring validity and reliability

Systematic reviews play a crucial role in evidence-based practices as they consolidate research findings to inform decision-making. However, it is essential to assess the quality of systematic reviews to prevent biased or inaccurate conclusions. This paper underscores the importance of adhering to recognized guidelines, such as the PRISMA statement and Cochrane Handbook. These recommendations advocate for systematic approaches and emphasize the documentation of critical components, including the search strategy and study selection. A thorough evaluation of methodologies, research quality, and overall evidence strength is essential during the appraisal process. Identifying potential sources of bias and review limitations, such as selective reporting or trial heterogeneity, is facilitated by tools like the Cochrane Risk of Bias and the AMSTAR 2 checklist. The assessment of included studies emphasizes formulating clear research questions and employing appropriate search strategies to construct robust reviews. Relevance and bias reduction are ensured through meticulous selection of inclusion and exclusion criteria. Accurate data synthesis, including appropriate data extraction and analysis, is necessary for drawing reliable conclusions. Meta-analysis, a statistical method for aggregating trial findings, improves the precision of treatment impact estimates. Systematic reviews should consider crucial factors such as addressing biases, disclosing conflicts of interest, and acknowledging review and methodological limitations. This paper aims to enhance the reliability of systematic reviews, ultimately improving decision-making in healthcare, public policy, and other domains. It provides academics, practitioners, and policymakers with a comprehensive understanding of the evaluation process, empowering them to make well-informed decisions based on robust data.

Sponsorship bias in published pharmacoeconomic evaluations of national reimbursement negotiation drugs in China: a systematic review

BACKGROUND

China's National Reimbursement Drug List (NRDL) has become the primary route for drug reimbursement in China. More recently, the authority has made pharmacoeconomic evaluation an integral part of the application for NRDL inclusion. The underlying financial conflict of interests (FCOI) of pharmacoeconomic evaluations, however, has the potential to influence evidence generated and thus subsequent decision-making yet remains poorly understood.

METHODS

We searched for studies published between January 2012 and January 2022 on the 174 drugs added to the 2017-2020 NRDLs after successful negotiation. We categorised the study's FCOI status into no funding, industry funding, non-profit funding and multiple fundings based on authors' disclosure and assessed the reporting quality of included studies using the Consolidated Health Economic Evaluation Reporting Standards 2022 checklist. We compiled descriptive statistics of funding types and study outcomes using t-tests and χ2 tests and conducted multivariate regression analysis.

RESULTS

We identified 378 records and our final sample included 92 pharmacoeconomic evaluations, among which 69.6% were conducted with at least one funding source. More than half (57.6%) of the evaluations reached favourable conclusions towards the intervention drug and 12.6% reached a dominant result of the intervention drug over the comparison from model simulation. The reporting quality of included studies ranged from 19 to 25 (on a scale of 28), with an average of 22.3. The statistical tests indicated that industry-funded studies were significantly more likely to conclude that the intervention therapy was economical (p<0.01) and had a significantly higher proportion of resulting target drug economically dominated the comparison drug (p<0.05).

CONCLUSION

The study revealed that FCOI bias is common in published pharmacoeconomic evaluations conducted in Chinese settings and could significantly influence the study's economical results and conclusions through various mechanisms. Multifaceted efforts are needed to improve transparency, comparability and reporting standardisation.

The methodological quality assessment of systematic reviews/meta-analyses of chronic prostatitis/chronic pelvic pain syndrome using AMSTAR2

BACKGROUND

This study aimed to assess the methodological quality of the systematic reviews/meta-analyses (SRs/MAs) of chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS) using A Measurement Tool to Assess systematic Reviews (AMSTAR2) and to explore the potential influencing factors.

METHODS

PubMed, EMBASE and Cochrane Library databases were searched for relevant studies. AMSTAR2 was used for evaluating the methodological quality of eligible SRs/MAs. Differences between methodological characteristics of SRs/MAs were compared using chi-square tests. The intra-class correlation coefficient (ICC) was used to assess reviewer agreement in the pre-experiment. Multivariate regression analysis was used to identify potential factors affecting methodological quality.

RESULTS

A total of 45 SRs/MAs were included. After AMSTAR2 evaluation, only two (4.4%) of 45 SRs/MAs were moderate, three (6.7%) were rated as low quality, and the remainder 40 (88.9%) were rated as critically low quality. Among the 16 items of AMSTAR2, item 3 and item 10 had the poorest adherence. Item 4 received the most significant number of "Partial Yes" responses. Univariable analysis indicated that there were significant differences in methodological quality in SRs between different continents (P = 0.027) as well as between preregistered SRs and those that were not (P = 0.004). However, in multivariate analysis, there was no significant association between methodological quality and the following research characteristics: publication year, continent, whether reporting followed Preferred Reporting Items for Systematic Reviews (PRISMA), preregistration, funding support, randomized controlled trials (RCT) enrollment, whether SR was published in the Cochrane Database of Systematic Reviews (CDSR), and whether with meta-analysis. Additionally, subgroup analysis based on interventional SRs/MAs showed that continent was independently associated with the methodological quality of SRs/MAs of CP/CPPS via univariable and multivariate analysis.

CONCLUSIONS

Our study demonstrates that the methodological quality of SRs/MAs of CP/CPPS was generally poor. SRs/MAs of CP/CPPS should adopt the AMSTAR2 to enhance their methodological quality.

Conflict of interest and risk of bias in systematic reviews on methylphenidate for attention-deficit hyperactivity disorder: a cross-sectional study

BACKGROUND

Systematic reviews (SRs) are pivotal to evidence-based medicine, yet there is limited research on conflicts of interest in SRs. Our aim was to investigate financial conflicts of interest and risk of bias (RoB) in SRs of a well-defined clinical topic.

METHODS

A librarian searched Medline, Cochrane Library, Embase, and PsycINFO for SRs investigating the effect of methylphenidate on ADHD in December 2020. The selection process adhered to the PRISMA guidelines. Two blinded reviewers independently searched open websites, including other publications, for information on financial conflicts of interest of all authors of the included SRs. A time limit of 3 years before or after the index SR was adopted. Declarations on conflict of interest were extracted from the included SRs for comparison. ROBIS was used for RoB assessment.

RESULTS

Out of 44 SRs included, 15 (34%) declared conflict of interest, 27 (61%) did not, and a declaration of conflict of interest was missing for 2 (5%). On open websites, conflict of interest was found for at least one author of 23 (52%) SRs: disclosed in 15 (34%) and not disclosed in 8 (18%) SRs. Seven (16%) SRs had low, 36 (82%) had high, and 1 (2%) had unclear RoB. Among SRs with financial conflict of interest found in open sources, 6/22 (27%) had low RoB compared to 1/21 (5%) if no such conflict of interest was identified. Among SRs with financial conflict of interest identified, 1/6 (17%) at low RoB did not disclose their conflict of interest, whereas the corresponding proportion among SRs at high RoB was 7/16 (44%). Eight (18%) SRs presented conflict of interest disclosed in the included primary studies. Four of them (50%) had low RoB, compared to 3/36 (8%) for SRs not reporting on this aspect.

CONCLUSION

Financial conflict of interest was underreported in 18% of the SRs using our reference standard, and overall it was present for every second SR. This group embraced both SRs at low RoB disclosing conflict of interest and SRs at high RoB not disclosing their conflict of interest. Further studies to explore this heterogeneity are warranted.

Tip of the Iceberg? Country- and Company-Level Analysis of Drug Company Payments for Research and Development in Europe

BACKGROUND

Creating new therapies often involves drug companies paying healthcare professionals and institutions for research and development (R&D) activities, including clinical trials. However, industry sponsorship can create conflicts of interest (COIs). We analysed approaches to drug company R&D payment disclosure in European countries and the distribution of R&D payments at the country and company level.

METHODS

Using documentary sources and a stakeholder survey we identified country- regulatory approaches to R&D payment disclosure. We reviewed company-level descriptions of disclosure practices in the United Kingdom, a country with a major role in Europe's R&D. We obtained country-level R&D payment data from industry trade groups and public authorities and company-level data from eurosfordocs.eu, a publicly available payments database. We conducted content analysis and descriptive statistical analysis.

RESULTS

In 32 of 37 studied countries, all R&D payments were reported without named recipients, following a self-regulatory approach developed by the industry. The methodological descriptions from 125 companies operating in the United Kingdom suggest that within the self-regulatory approach companies had much leeway in deciding what activities and payments were considered as R&D. In five countries, legislation mandated the disclosure of R&D payment recipients, but only in two were payments practically identifiable and analysable. In 17 countries with available data, R&D constituted 19%-82% of all payments reported, with self-regulation associated with higher shares. Available company-level data from three countries with self-regulation suggests that R&D payments were concentrated by big funders, and some companies reported all, or nearly all, payments as R&D.

CONCLUSION

The lack of full disclosure of R&D payments in countries with industry self-regulation leaves considerable sums of money unaccounted for and potentially many COIs undetected. Disclosure mandated by legislation exists in few countries and rarely enhances transparency practically. We recommend a unified European approach to R&D payment disclosure, including clear definitions and a centralised database.

How are declarations of interest working? A cross-sectional study in declarations of interest in healthcare practice in Scotland and England in 2020/2021

OBJECTIVE

To understand arrangements for healthcare organisations' declarations of staff interest in Scotland and England in the context of current recommendations.

DESIGN

Cross-sectional study of a random selection of National Health Service (NHS) hospital registers of interest by two independent observers in England, all NHS Boards in Scotland and a random selection of Clinical Commissioning Groups (CCGs) in England.

SETTING

NHS Trusts in England (NHSE), NHS Boards in Scotland, CCGs in England, and private healthcare organisations.

PARTICIPANTS

Registers of declarations of interest published in a random sample of 67 of 217 NHS Trusts, a random sample of 15 CCGs of in England, registers held by all 14 NHS Scotland Boards and a purposeful selection of private hospitals/clinics in the UK.

MAIN OUTCOME MEASURES

Adherence to NHSE guidelines on declarations of interests, and comparison in Scotland.

RESULTS

76% of registers published by Trusts did not routinely include all declaration of interest categories recommended by NHS England. In NHS Scotland only 14% of Boards published staff registers of interest. Of these employee registers (most obtained under Freedom of Information), 27% contained substantial retractions. In England, 96% of CCGs published a Gifts and Hospitality register, with 67% of CCG staff declaration templates and 53% of governor registers containing full standard NHS England declaration categories. Single organisations often held multiple registers lacking enough information to interpret them. Only 35% of NHS Trust registers were organised to enable searching. None of the private sector organisations studied published a comparable declarations of interest register.

CONCLUSION

Despite efforts, the current system of declarations frequently lacks ability to meaningfully obtain complete healthcare professionals' declaration of interests.

Correlation analysis of financial conflicts of interest and favourability of results or conclusions in addiction medicine systematic reviews and meta-analysis

OBJECTIVE

To quantify conflicts of interest, assess the accuracy of authors self-reporting them, and examine the association between conflicts of interest and favourability of results and discussions in addiction medicine systematic reviews.

DESIGN

A search was performed on Medline (Ovid) from January 2016 to 25 April 2020 to locate systematic reviews and meta-analyses focused on treatments of addiction disorders using a systematic search strategy. Data were extracted from each systematic review, including conflict of interest statements, authorship characteristics and the favourability of the results/conclusion sections. A search algorithm was used to identify any undisclosed conflicts of interest on the Open Payments Database (Dollars for Docs), Dollars for Profs, Google Patents/United States Patent and Trade Office, and prior conflict of interest statements in other published works from these authors.

RESULTS

The search identified 127 systematic reviews, representing 665 unique authors. Of the 127 studies, 81 reported no authors with conflicts of interest, 28 with 1 or more conflict, and 18 had no conflict of interest statement. Additional non-disclosed conflicts of interest were found for 34 authors. There were 69 reviews that had at least one author with a conflict of interest. Of the 69 reviews, 14 (20.3%) reported favourable results and 26 (37.7%) reported favourable discussion/conclusions with no statistically significant association. A subanalysis was performed on publications with only US authors (51) with 35 (68.9%) having at least 1 conflict of interest. US authored studies that had a conflict of interest favoured the results (p = <0.001) and discussion/conclusion (p = 0.018) more often.

CONCLUSION

Although multiple undisclosed financial conflicts of interest were found, there was no correlation with the favourability of the results or discussion/conclusions across all addiction medicine systematic reviews. Further research needs to be done on US-based publications and encourage disclosure systems worldwide to provide more accurate reporting.

Impact of industry sponsorship on the quality of systematic reviews of vaccines: a cross-sectional analysis of studies published from 2016 to 2019

BACKGROUND

Systematic reviews (SRs) provide the highest level of evidence and inform evidence-based decision making in health care. Earlier studies found association with industry to be negatively associated with methodological quality of SRs. However, this has not been investigated in SRs on vaccines.

METHODS

We performed a systematic literature search using MEDLINE and EMBASE in March 2020. The results were restricted to those published between 2016 and 2019 with no language restrictions. Study characteristics were extracted by one person and checked by an experienced reviewer. The methodological quality of the SRs was assessed with the AMSTAR 2 tool by multiple reviewers after a calibration exercise was performed. A summary score for each SR was calculated. The Mann-Whitney U test and Fisher's exact test were performed to compare both groups.

RESULTS

Out of 185 SRs that met all inclusion criteria, 27 SRs were industry funded. Those were matched with 30 non-industry funded SRs resulting in a total sample size of 57. The mean AMSTAR 2 summary score across all SRs was 0.49. Overall, the median AMSTAR 2 summary score was higher for the non-industry funded SRs than for the industry-funded SRs (0.62 vs. 0.36; p < .00001). Lower ratings for industry funded SRs were consistent across all but one AMSTAR 2 item, though significantly lower only for three specific items.

CONCLUSION

The methodological quality of SRs in vaccination is comparable to SRs in other fields, while it is still suboptimal. We are not able to provide a satisfactory explanation why industry funded SRs had a lower methodological quality than non-industry funded SRs over recent years. Industry funding is an important indicator of methodological quality for vaccine SRs and should be carefully considered when appraising SR quality.

Conflict of Interest Policies at Medical Schools and Teaching Hospitals: A Systematic Review of Cross-sectional Studies

BACKGROUND

This systematic review aims to estimate the proportion of medical schools and teaching hospitals with conflicts of interest (COI) policies for health research and education, to describe the provisions included in the policies and their impact on research outputs and educational quality or content.

METHODS

Experimental and observational studies reporting at least one of the above mentioned aims were included irrespective of language, publication type or geographical setting. MEDLINE, Scopus, Embase and the Cochrane Methodology Register were searched from inception to March 2020. Methodological study quality was assessed using an amended version of the Joanna Briggs Institute's checklist for prevalence studies.

RESULTS

Twenty-two cross-sectional studies were included; all were conducted in high-income countries. Of these, 20 studies estimated the prevalence of COI policies, which ranged from 5% to 100% (median: 85%). Twenty studies assessed the provisions included in COI policies with different assessment methods. Of these, nine analysed the strength of the content of medical schools' COI policies using various assessment tools that looked at a range of policy domains. The mean standardised summary score of policy strength ranged from 2% to 73% (median: 30%), with a low score indicating a weak policy. North American institutions more frequently had COI policies and their content was rated as stronger than policies from European institutions. None of the included studies assessed the impact of COI policies on research outputs or educational quality or content.

CONCLUSION

Prevalence of COI policies at medical schools and teaching hospitals varied greatly in high-income countries. No studies estimated the prevalence of policies in low to middle-income countries. The content of COI policies varied widely and while most European institutions ranked poorly, in North America more medical schools had strong policies. No studies were identified on impact of COI policies on research outputs and educational quality or content.

Addressing Conflicts of Interest and Conflicts of Commitment in Public Advocacy and Policy Making on CRISPR/Cas-Based Human Genome Editing

Leading experts on CRISPR/Cas-based genome editing-such as 2020 Nobel laureates Jennifer Doudna and Emmanuelle Charpentier-are not only renowned specialists in their fields, but also public advocates for upcoming regulatory frameworks on CRISPR/Cas. These frameworks will affect large portions of biomedical research on human genome editing. In advocating for particular ways of handling the risks and prospects of this technology, high-profile scientists not only serve as scientific experts, but also as moral advisers. The majority of them currently intend to bring about a "responsible pathway" toward human genome interventions in clinical therapy. Engaging in advocacy for such a pathway, they issue moral judgments on the risks and benefits of this new technology. They declare that there actually is a responsible pathway, they draft resolutions on temporary moratoria, they make judgments on which groups and individuals are credible and should participate in public and semi-public debates, so they also set the standards for deciding who counts as well-informed, as well as the standards of evidence for adopting or rejecting research policies. This degree of influence on public debates and policy making is, at the very least, noteworthy. This contribution sounds a note of caution with regard to the endeavor of a responsible pathway to human genome editing and in particular scrutinizes the legitimacy of expert-driven research policies given commercial conflicts of interest and conflicts of commitment among first-rank scholars.

Effectiveness of Written Dietary Advice for Improving Blood Lipids in Primary Care Adults-A Pragmatic Randomized Controlled Trial (MYDICLIN)

Lifestyle management is the first line of treatment for moderately elevated blood lipids in healthy individuals. We investigated the effectiveness of providing food-based written advice for lowering low-density lipoprotein (LDL) cholesterol (intervention) or triglycerides (control) in a pragmatic randomized controlled trial with two parallel arms from 2018-2019 at a rural primary health care center. We sent feedback letters after 3 weeks and 6 months. Out of the 113 adult primary care patients randomized, 112 completed the study. There were no differences between the intervention and control groups for changes in LDL cholesterol after 3 weeks (mean ± standard deviation -0.21 ± 0.38 vs. -0.11 ± 0.34 mmol/L, p = 0.45) or 6 months (-0.05 ± 0.47 vs. 0.02 ± 0.41 mmol/L, p = 0.70) (primary outcome). Following the advice to consume plant sterols and turmeric was associated with a reduction in LDL cholesterol after 3 weeks. Following the advice to consume less carbohydrates was associated with reduced triglycerides. In the intervention arm, 14 individuals (25%) reduced their LDL cholesterol by ≥10% after three weeks. Their reduction was attenuated but maintained after six months (-7.1 ± 9.2% or -0.31 ± 0.38 mmol/L, p = 0.01 compared with baseline). They differed only in higher adherence to the advice regarding turmeric. In conclusion, this undemanding intervention had little effect on blood lipids for most individuals.

Alcohol, cardiovascular disease and industry funding: A co-authorship network analysis of systematic reviews

BACKGROUND

Alcohol's effects on heart health is the site of a major scientific controversy. We conducted a co-authorship network analysis of systematic reviews on the impacts on alcohol on cardiovascular disease (CVD) in order to investigate patterns of co-authorship in the literature, with particular attention given to industry funding.

METHODS

We used Epistemonikos to identify systematic reviews. Review characteristics, influential authors, co-authorship subnetworks, prior histories of alcohol industry funding, study outcomes and citations were investigated.

RESULTS

60 systematic reviews with 231 unique authors met our inclusion criteria. 14 systematic reviews were undertaken by authors with histories of alcohol industry funding, including 5 that were funded directly by the alcohol industry itself. All 14 such reviews identified a cardioprotective effect of alcohol. These formed distinct co-authorship subnetworks within the literature. Of reviews by authors with no prior histories of alcohol industry funding, the findings were mixed, with 54% (25/46) concluding there was evidence of health protective effects. These two groups of reviews differed in other respects. Those with industry funding were more likely to study broader outcomes such as 'cardiovascular disease' or 'coronary heart disease' as opposed to specific CVD issues such as hypertension or stroke (93% [13/14] versus 41% [19/46]) (chi-squared 12.4, p < 0.001) and have more included studies (mean of 29 versus 20). They were also more widely cited by others. Over time the proportions of systematic reviews on CVD and alcohol undertaken by authors with no prior histories of alcohol industry funding has increased.

CONCLUSIONS

Systematic reviews undertaken by authors with histories of alcohol industry funding were more likely to study broader outcomes, and be cited more widely, and exclusively reported favorable conclusions.

Are Corporations Re-Defining Illness and Health? The Diabetes Epidemic, Goal Numbers, and Blockbuster Drugs

While pharmaceutical industry involvement in producing, interpreting, and regulating medical knowledge and practice is widely accepted and believed to promote medical innovation, industry-favouring biases may result in prioritizing corporate profit above public health. Using diabetes as our example, we review successive changes over forty years in screening, diagnosis, and treatment guidelines for type 2 diabetes and prediabetes, which have dramatically expanded the population prescribed diabetes drugs, generating a billion-dollar market. We argue that these guideline recommendations have emerged under pervasive industry influence and persisted, despite weak evidence for their health benefits and indications of serious adverse effects associated with many of the drugs they recommend. We consider pharmaceutical industry conflicts of interest in some of the research and publications supporting these revisions, and in related standard-setting committees and oversight panels. We raise concern over the long-term impact of these multifaceted involvements. Rather than accept industry conflicts of interest as normal, needing only to be monitored and managed, we suggest challenging that normalcy, and ask: what are the real costs of tolerating such industry participation? We urge the development of a broader focus to fully understand and curtail the systemic nature of industry's influence over medical knowledge and practice.

Conflicts of Interest Among Authors of Systematic Reviews and Meta-analyses Investigating Interventions for Melanoma: Cross-sectional Literature Study

BACKGROUND

Previous studies have highlighted the potential influence that industry relationships may have on the outcomes of medical research.

OBJECTIVE

We aimed to determine the prevalence of author conflicts of interest (COIs) in systematic reviews focusing on melanoma interventions, as well as to determine whether the presence of these COIs were associated with an increased likelihood of reporting favorable results and conclusions.

METHODS

This cross-sectional study included systematic reviews with or without meta-analyses focusing on interventions for melanoma. We searched MEDLINE and Embase for eligible systematic reviews published between September 1, 2016, and June 2, 2020. COI disclosures were cross-referenced with information from the CMS (Centers for Medicare & Medicaid Services) Open Payments database, Dollars for Profs, Google Patents, the United States Patent and Trademark Office, and previously published COI disclosure statements. Results were quantified using descriptive statistics, and relationships were evaluated by Fisher exact tests.

RESULTS

Of the 23 systematic reviews included in our sample, 12 (52%) had at least one author with a COI. Of these 12 reviews, 7 (58%) reported narrative results favoring the treatment group and 9 (75%) reported conclusions favoring the treatment group. Of the 11 systematic reviews without a conflicted author, 4 (36%) reported results favoring the treatment group and 5 (45%) reported conclusions favoring the treatment group. We found no significant association between the presence of author COIs and the favorability of results (P=.53) or conclusions (P=.15).

CONCLUSIONS

Author COIs did not appear to influence the outcomes of systematic reviews regarding melanoma interventions. Clinicians and other readers of dermatology literature should be cognizant of the influence that industry may have on the nature of reported outcomes, including those from systematic reviews and meta-analyses.

PRISMA 2020 explanation and elaboration: updated guidance and exemplars for reporting systematic reviews

The methods and results of systematic reviews should be reported in sufficient detail to allow users to assess the trustworthiness and applicability of the review findings. The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) statement was developed to facilitate transparent and complete reporting of systematic reviews and has been updated (to PRISMA 2020) to reflect recent advances in systematic review methodology and terminology. Here, we present the explanation and elaboration paper for PRISMA 2020, where we explain why reporting of each item is recommended, present bullet points that detail the reporting recommendations, and present examples from published reviews. We hope that changes to the content and structure of PRISMA 2020 will facilitate uptake of the guideline and lead to more transparent, complete, and accurate reporting of systematic reviews.

Preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts): checklist, explanation, and elaboration

For many users of the biomedical literature, abstracts may be the only source of information about a study. Hence, abstracts should allow readers to evaluate the objectives, key design features, and main results of the study. Several evaluations have shown deficiencies in the reporting of journal and conference abstracts across study designs and research fields, including systematic reviews of diagnostic test accuracy studies. Incomplete reporting compromises the value of research to key stakeholders. The authors of this article have developed a 12 item checklist of preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts). This article presents the checklist, examples of complete reporting, and explanations for each item of PRISMA-DTA for Abstracts.

Association between conflicts of interest and favourable recommendations in clinical guidelines, advisory committee reports, opinion pieces, and narrative reviews: systematic review

OBJECTIVE

To investigate the association between conflicts of interest and favourable recommendations in clinical guidelines, advisory committee reports, opinion pieces, and narrative reviews.

DESIGN

Systematic review.

ELIGIBILITY CRITERIA

Studies that compared the association between conflicts of interest and favourable recommendations of drugs or devices (eg, recommending a drug) in clinical guidelines, advisory committee reports, opinion pieces (eg, editorials), or narrative reviews.

DATA SOURCES

PubMed, Embase, Cochrane Methodology Register (from inception to February 2020), reference lists, Web of Science, and grey literature.

DATA EXTRACTION AND ANALYSIS

Two authors independently extracted data and assessed the methodological quality of the studies. Pooled relative risks and 95% confidence intervals were estimated using random effects models (relative risk >1 indicates that documents with conflicts of interest more often had favourable recommendations than documents with no conflicts of interest). Financial and non-financial conflicts of interest were analysed separately, and the four types of documents were analysed separately (preplanned) and combined (post hoc).

RESULTS

21 studies that analysed 106 clinical guidelines, 1809 advisory committee reports, 340 opinion pieces, and 497 narrative reviews were included. Unpublished data were received for 11 studies (eight full datasets and three summary datasets). 15 studies showed risk of confounding because the compared documents could differ in factors other than conflicts of interest (eg, different drugs used for different populations). The relative risk for associations between financial conflicts of interest and favourable recommendations for clinical guidelines was 1.26 (95% confidence interval 0.93 to 1.69; four studies of 86 clinical guidelines), for advisory committee reports was 1.20 (0.99 to 1.45; four studies of 629 advisory committee reports), for opinion pieces was 2.62 (0.91 to 7.55; four studies of 284 opinion pieces), and for narrative reviews was 1.20 (0.97 to 1.49; four studies of 457 narrative reviews). An analysis of all four types of documents combined supported these findings (1.26, 1.09 to 1.44). In one study that investigated specialty interests, the association between including radiologists as authors of guidelines and recommending routine breast cancer was: relative risk 2.10, 95% confidence interval 0.92 to 4.77; 12 clinical guidelines).

CONCLUSIONS

We interpret our findings to indicate that financial conflicts of interest are associated with favourable recommendations of drugs and devices in clinical guidelines, advisory committee reports, opinion pieces, and narrative reviews. Limitations of this review were risk of confounding in the included studies and the statistical imprecision of individual analyses of each document type. It is not certain whether non-financial conflicts of interest influence recommendations.

SYSTEMATIC REVIEW REGISTRATION

Cochrane Methodology Review Protocol MR000040.

Conflicts of interest in clinical guidelines, advisory committee reports, opinion pieces, and narrative reviews: associations with recommendations

BACKGROUND

Treatment and diagnostic recommendations are often made in clinical guidelines, reports from advisory committee meetings, opinion pieces such as editorials, and narrative reviews. Quite often, the authors or members of advisory committees have industry ties or particular specialty interests which may impact on which interventions are recommended. Similarly, clinical guidelines and narrative reviews may be funded by industry sources resulting in conflicts of interest.

OBJECTIVES

To investigate to what degree financial and non-financial conflicts of interest are associated with favourable recommendations in clinical guidelines, advisory committee reports, opinion pieces, and narrative reviews.

SEARCH METHODS

We searched PubMed, Embase, and the Cochrane Methodology Register for studies published up to February 2020. We also searched reference lists of included studies, Web of Science for studies citing the included studies, and grey literature sources.

SELECTION CRITERIA

We included studies comparing the association between conflicts of interest and favourable recommendations of drugs or devices (e.g. recommending a particular drug) in clinical guidelines, advisory committee reports, opinion pieces, or narrative reviews.

DATA COLLECTION AND ANALYSIS

Two review authors independently included studies, extracted data, and assessed risk of bias. When a meta-analysis was considered meaningful to synthesise our findings, we used random-effects models to estimate risk ratios (RRs) with 95% confidence intervals (CIs), with RR > 1 indicating that documents (e.g. clinical guidelines) with conflicts of interest more often had favourable recommendations. We analysed associations for financial and non-financial conflicts of interest separately, and analysed the four types of documents both separately (pre-planned analyses) and combined (post hoc analysis).

MAIN RESULTS

We included 21 studies analysing 106 clinical guidelines, 1809 advisory committee reports, 340 opinion pieces, and 497 narrative reviews. We received unpublished data from 11 studies; eight full data sets and three summary data sets. Fifteen studies had a risk of confounding, as they compared documents that may differ in other aspects than conflicts of interest (e.g. documents on different drugs used for different populations). The associations between financial conflicts of interest and favourable recommendations were: clinical guidelines, RR: 1.26, 95% CI: 0.93 to 1.69 (four studies of 86 clinical guidelines); advisory committee reports, RR: 1.20, 95% CI: 0.99 to 1.45 (four studies of 629 advisory committee reports); opinion pieces, RR: 2.62, 95% CI: 0.91 to 7.55 (four studies of 284 opinion pieces); and narrative reviews, RR: 1.20, 95% CI: 0.97 to 1.49 (four studies of 457 narrative reviews). An analysis combining all four document types supported these findings (RR: 1.26, 95% CI: 1.09 to 1.44). One study investigating specialty interests found that the association between including radiologist guideline authors and recommending routine breast cancer screening was RR: 2.10, 95% CI: 0.92 to 4.77 (12 clinical guidelines).

AUTHORS' CONCLUSIONS

We interpret our findings to indicate that financial conflicts of interest are associated with favourable recommendations of drugs and devices in clinical guidelines, advisory committee reports, opinion pieces, and narrative reviews. However, we also stress risk of confounding in the included studies and the statistical imprecision of individual analyses of each document type. It is not certain whether non-financial conflicts of interest impact on recommendations.

Are conflict of interest declarations appropriate to allow sufficient consideration of potential bias in presentations?

Background

Potential conflicts of interest (CoI) are common in medical research, necessitating the use of CoI declarations. There is currently no consensus document or external authority guiding CoI declarations in conference settings, resulting in declarations of variable quality and utility.

Methods

We explored four CoI declaration parameters (sufficient slide display time; the presence of any verbal explanation pertaining to relevant CoI; the use of an adequate font size; and whether the nature and relevance of the CoI was described). Parameters were graded from one to three points, with the sum of parameters providing an overall declaration quality out of 12. We then applied this scoring system to recordings of presentations from the British Cardiovascular Society (BCS) annual conference 2018 which were available online.

Results

Sixty-nine presentations were suitable for inclusion, of which 47 (68%) contained a CoI statement. Thirty-six of the 47 (77%) presentations declared that they had no CoI. In the remaining 11 (23%) with reported CoI, the median time spent displaying CoI was 1 second (interquartile range (IQR) 0.7-3.3). The median quality score for presentations was 7 (IQR 6-10).

Conclusion

This study demonstrates utility in considering aspects of CoI declarations at conferences to improve transparency.

A tutorial on methodological studies: the what, when, how and why

BACKGROUND

Methodological studies - studies that evaluate the design, analysis or reporting of other research-related reports - play an important role in health research. They help to highlight issues in the conduct of research with the aim of improving health research methodology, and ultimately reducing research waste.

MAIN BODY

We provide an overview of some of the key aspects of methodological studies such as what they are, and when, how and why they are done. We adopt a "frequently asked questions" format to facilitate reading this paper and provide multiple examples to help guide researchers interested in conducting methodological studies. Some of the topics addressed include: is it necessary to publish a study protocol? How to select relevant research reports and databases for a methodological study? What approaches to data extraction and statistical analysis should be considered when conducting a methodological study? What are potential threats to validity and is there a way to appraise the quality of methodological studies?

CONCLUSION

Appropriate reflection and application of basic principles of epidemiology and biostatistics are required in the design and analysis of methodological studies. This paper provides an introduction for further discussion about the conduct of methodological studies.