The quality of reporting of randomized controlled trials in solid organ transplantation

Effect of Sirolimus vs. Everolimus on CMV-Infections after Kidney Transplantation-A Network Meta-Analysis

(1) Background: Following renal transplantation, infection with cytomegalovirus (CMV) is a common and feared complication. mTOR-inhibitor (mTOR-I) treatment, either alone or in combination with calcineurininhibitors (CNIs), significantly reduces the CMV incidence after organ transplantation. As of now, there is no information on which mTOR-I, sirolimus (SIR) or everolimus (ERL), has a stronger anti-CMV effect. (2) Methods: The current literature was searched for prospective randomized controlled trials in renal transplantation. There were 1164 trials screened, of which 27 could be included (11,655 pts.). We performed a network meta-analysis to analyze the relative risk of different types of mTOR-I treatment on CMV infection 12 months after transplantation compared to CNI treatment. (3) Results: Four different types of mTOR-I treatment were analyzed in network meta-analyses—SIR mono, ERL mono, SIR with CNI, ERL with CNI. The mTOR-I treatment with the strongest anti-CMV effect compared to a regular CNI treatment was ERL in combination with a CNI (relative risk (RR) 0.27, confidence interval (CI) 0.22−0.32, p < 0.0001). The other mTOR-I therapy groups showed a slightly decreased anti-CMV efficacy (SIR monotherapy (mono): RR 0.35, CI 0.22−0.57, p < 0.001; SIR with CNI: RR 0.43, CI 0.29−0.64, p < 0.0001; ERL mono: RR 0.46, CI 0.22−0.93, p = 0.031). (4) Conclusions: The anti-CMV effect of both mTOR-Is (SRL and ERL) is highly effective, irrespective of the combination with other immunosuppressive drugs. Certain differences with respect to the potency against the CMV could be found between SRL and ERL. Data gained from this analysis seem to support that a combination of ERL and CNI has the most potent anti-CMV efficacy.

Systematic review and meta-analyses of studies analysing instructions to authors from 1987 to 2017

To gain insight into changes of scholarly journals' recommendations, we conducted a systematic review of studies that analysed journals' Instructions to Authors (ItAs). We summarised results of 153 studies, and meta-analysed how often ItAs addressed: 1) authorship, 2) conflicts of interest, 3) data sharing, 4) ethics approval, 5) funding disclosure, and 6) International Committee of Medical Journal Editors' Uniform Requirements for Manuscripts. For each topic we found large between-study heterogeneity. Here, we show six factors that explained most of that heterogeneity: 1) time (addressing of topics generally increased over time), 2) country (large differences found between countries), 3) database indexation (large differences found between databases), 4) impact factor (topics were more often addressed in highest than in lowest impact factor journals), 5) discipline (topics were more often addressed in Health Sciences than in other disciplines), and 6) sub-discipline (topics were more often addressed in general than in sub-disciplinary journals).

Nutritional supplements and mother's milk composition: a systematic review of interventional studies

Background

This study aims to systematically review the effects of maternal vitamin and/or mineral supplementation on the content of breast milk.

Methods

We systematically searched electronic databases including Medline via PubMed, Scopus and ISI Web of Science till May 24, 2018. The following terms were used systematically in all mentioned databases: (“human milk” OR “breast milk” OR “breast milk composition” OR “human breast milk composition” OR “composition breast milk” OR “mother milk” OR “human breast milk” OR “maternal milk”) AND (“vitamin a” OR “retinol” OR “retinal” OR “retinoic acid” OR “beta-carotene” OR “beta carotene” OR “ascorbic acid” OR “l-ascorbic acid” OR “l ascorbic acid” OR “vitamin c” OR “vitamin d” OR “cholecalciferol” OR “ergocalciferol” OR “calciferol” OR “vitamin e” OR “tocopherol” OR “tocotrienol” OR “alpha-tocopherol” OR “alpha tocopherol” OR “α-tocopherol” OR “α tocopherol” OR “vitamin k” OR “vitamin b” OR “vitamin b complex” OR “zinc” OR “iron” OR “copper” Or “selenium” OR “manganese” OR “magnesium”) and we searched Medline via Medical subject Headings (MeSH) terms. We searched Google Scholar for to increase the sensitivity of our search. The search was conducted on human studies, but it was not limited to the title and abstract. Methodological quality and risk of bias of included studies were evaluated by Jadad scale and Cochrane risk of bias tools, respectively.

Results

This review included papers on three minerals (zinc, iron, selenium) and 6 vitamins (vitamin A, B, D, C, E and K) in addition to multi-vitamin supplements. Although studies had different designs, e.g. not using random allocation and/or blinding, our findings suggest that maternal use of some dietary supplements, including vitamin A, D, vitamin B1, B2 and vitamin C might be reflected in human milk. Vitamin supplements had agreater effect on breast milk composition compared to minerals. Higher doses of supplements showed higher effects and they were reflected more in colostrum than in the mature milk.

Conclusion

Maternal dietary vitamin and/or mineral supplementation, particularly fat- soluble vitamins, vitamin B1, B2 and C might be reflected in the breast milk composition. No difference was found between mega dose and single dose administration of minerals.

Industry-funded versus non-profit-funded critical care research: a meta-epidemiological overview

Purpose

To study the landscape of funding in intensive care research and assess whether the reported outcomes of industry-funded randomized controlled trials (RCTs) are more favorable.

Methods

We systematically assembled meta-analyses evaluating any type of intervention in the critical care setting and reporting the source of funding for each included RCT. Furthermore, when the intervention was a drug or biologic, we searched also the original RCT articles, when their funding information was unavailable in the meta-analysis. We then qualitatively summarized the sources of funding. For binary outcomes, separate summary odds ratios were calculated for trials with and without industry funding. We then calculated the ratio of odds ratios (RORs) and the summary ROR (sROR) across topics. ROR < 1 implies that the experimental intervention is relatively more favorable in trials with industry funding compared with trials without industry funding. For RCTs included in the ROR analysis, we also examined the conclusions of their abstract.

Results

Across 67 topics with 568 RCTs, 88 were funded by industry and another 73 had both industry and non-profit funding. Across 33 topics with binary outcomes, the sROR was 1.10 [95% CI (0.96–1.26), I² = 1%]. Conclusions were not significantly more commonly unfavorable for the experimental arm interventions in industry-funded trials (21.3%) compared with trials without industry funding (18.2%).

Conclusion

Industry-funded RCTs are the minority in intensive care. We found no evidence that industry-funded trials in intensive care yield more favorable results or are less likely to reach unfavorable conclusions.

Electronic supplementary material

The online version of this article (10.1007/s00134-018-5325-3) contains supplementary material, which is available to authorized users.

Effects of mTOR-Is on malignancy and survival following renal transplantation: A systematic review and meta-analysis of randomized trials with a minimum follow-up of 24 months

Background

mTOR-Is positively influence the occurrence and course of certain tumors after solid organ transplantation. The effect of mTOR-Is on the overall incidence of tumors irrespective of their origin is not entirely clear. Furthermore, conflicting data have been shown on mortality under mTOR-Is.

Methods

The current literature was searched for prospective randomized controlled renal transplantation trials. There were 1415 trials screened of which 13 could be included (pts. = 5924). A minimum follow-up of 24 months was mandatory for inclusion. Incidence of malignancies and patient survival was assessed in meta-analyses.

Results

The average follow-up of all trials was 40.6 months. Malignancy was significantly reduced under mTOR-Is compared to CNIs (RR 0.70, CI 0.49–0.99, p = 0.046). This effect remained stable when combined with CNIs (RR 0.58, CI 0.34–1.00, p = 0.05). When NMSCs were excluded the risk for malignancy remained significantly reduced under mTOR-I therapy (mono and combi) (RR 0.43, CI 0.24–0.77, p = 0.0046). Graft survival was minimally decreased under mTOR-Is (RR 0.99, CI 0.98–1.00, p = 0.054). This effect was abrogated when mTOR-Is were combined with CNIs (RR 0.99, CI 0.97–1.02, p = 0.50). Patient survival was not different (RR 1.00, CI 0.99–1.01, p = 0.54).

Conclusions

Posttransplant patients have a lower incidence of malignancy when treated with an mTOR-I no matter if it is used in combination with CNIs or not. This beneficial effect remains significant even when NMSCs are excluded. With currently used mTOR-I-based regimen patient and graft survival is not different compared to CNI therapies.

Current practice in methodology and reporting of the sample size calculation in randomised trials of hip and knee osteoarthritis: a protocol for a systematic review

Background

A key aspect of the design of randomised controlled trials (RCTs) is determining the sample size. It is important that the trial sample size is appropriately calculated. The required sample size will differ by clinical area, for instance, due to the prevalence of the condition and the choice of primary outcome. Additionally, it will depend upon the choice of target difference assumed in the calculation. Focussing upon the hip and knee osteoarthritis population, this study aims to systematically review how the trial size was determined for trials of osteoarthritis, on what basis, and how well these aspects are reported.

Methods

Several electronic databases (Medline, Cochrane library, CINAHL, EMBASE, PsycINFO, PEDro and AMED) will be searched to identify articles on RCTs of hip and knee osteoarthritis published in 2016. Articles will be screened for eligibility and data extracted independently by two reviewers. Data will be extracted on study characteristics (design, population, intervention and control treatments), primary outcome, chosen sample size and justification, parameters used to calculate the sample size (including treatment effect in control arm, level of variability in primary outcome, loss to follow-up rates). Data will be summarised across the studies using appropriate summary statistics (e.g. n and %, median and interquartile range). The proportion of studies which report each key component of the sample size calculation will be presented. The reproducibility of the sample size calculation will be tested.

Discussion

The findings of this systematic review will summarise the current practice for sample size calculation in trials of hip and knee osteoarthritis. It will also provide evidence on the completeness of the reporting of the sample size calculation, reproducibility of the chosen sample size and the basis for the values used in the calculation.

Trial registration

As this review was not eligible to be registered on PROSPERO, the summary information was uploaded to Figshare to make it publicly accessible in order to avoid unnecessary duplication amongst other benefits (https://doi.org/10.6084/m9.figshare.5009027.v1); Registered January 17, 2017.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2209-8) contains supplementary material, which is available to authorized users.

Characteristics of funding of clinical trials: cross-sectional survey and proposed guidance

OBJECTIVES

To provide a detailed and current characterisation of funding of a representative sample clinical trials. We also aimed to develop guidance for standardised reporting of funding information.

METHODS

We addressed the extent to which clinical trials published in 2015 in any of the 119 Core Clinical Journals included a statement on the funding source (eg, whether a not-for-profit organisation was supported by a private-for-profit organisation), type of funding, amount and role of funder. We used a stepwise approach to develop a guidance and an instrument for standardised reporting of funding information.

RESULTS

Of 200 trials, 178 (89%) included a funding statement, of which 171 (96%) reported being funded. Funding statements in the 171 funded trials indicated the source in 100%, amount in 1% and roles of funders in 50%. The most frequent sources were governmental (58%) and private-for-profit (40%). Of 54 funding statements in which the source was a not-for-profit organisation, we found evidence of undisclosed support of those from private-for-profit organisation(s) in 26 (48%). The most frequently reported roles of funders in the 171 funded trials related to study design (42%) and data analysis, interpretation or management (41%). Of 139 randomised controlled trials (RCTs) addressing pharmacological or surgical interventions, 29 (21%) reported information on the supplier of the medication or device. The proposed guidance addresses both the funding information that RCTs should report and the reporting process. Attached to the guidance is a fillable PDF document for use as an instrument for standardised reporting of funding information.

CONCLUSION

Although the majority of RCTs report funding, there is considerable variability in the reporting of funding source, amount and roles of funders. A standardised approach to reporting of funding information would address these limitations. Future research should explore the implications of funding by not-for-profit organisations that are supported by for-profit organisations.

Industry sponsorship and research outcome

BACKGROUND

Clinical research affecting how doctors practice medicine is increasingly sponsored by companies that make drugs and medical devices. Previous systematic reviews have found that pharmaceutical-industry sponsored studies are more often favorable to the sponsor's product compared with studies with other sources of sponsorship. A similar association between sponsorship and outcomes have been found for device studies, but the body of evidence is not as strong as for sponsorship of drug studies. This review is an update of a previous Cochrane review and includes empirical studies on the association between sponsorship and research outcome.

OBJECTIVES

To investigate whether industry sponsored drug and device studies have more favorable outcomes and differ in risk of bias, compared with studies having other sources of sponsorship.

SEARCH METHODS

In this update we searched MEDLINE (2010 to February 2015), Embase (2010 to February 2015), the Cochrane Methodology Register (2015, Issue 2) and Web of Science (June 2015). In addition, we searched reference lists of included papers, previous systematic reviews and author files.

SELECTION CRITERIA

Cross-sectional studies, cohort studies, systematic reviews and meta-analyses that quantitatively compared primary research studies of drugs or medical devices sponsored by industry with studies with other sources of sponsorship. We had no language restrictions.

DATA COLLECTION AND ANALYSIS

Two assessors screened abstracts and identified and included relevant papers. Two assessors extracted data, and we contacted authors of included papers for additional unpublished data. Outcomes included favorable results, favorable conclusions, effect size, risk of bias and whether the conclusions agreed with the study results. Two assessors assessed risk of bias of included papers. We calculated pooled risk ratios (RR) for dichotomous data (with 95% confidence intervals (CIs)).

MAIN RESULTS

Twenty-seven new papers were included in this update and in total the review contains 75 included papers. Industry sponsored studies more often had favorable efficacy results, RR: 1.27 (95% CI: 1.17 to 1.37) (25 papers) (moderate quality evidence), similar harms results RR: 1.37 (95% CI: 0.64 to 2.93) (four papers) (very low quality evidence) and more often favorable conclusions RR: 1.34 (95% CI: 1.19 to 1.51) (29 papers) (low quality evidence) compared with non-industry sponsored studies. Nineteen papers reported on sponsorship and efficacy effect size, but could not be pooled due to differences in their reporting of data and the results were heterogeneous. We did not find a difference between drug and device studies in the association between sponsorship and conclusions (test for interaction, P = 0.98) (four papers). Comparing industry and non-industry sponsored studies, we did not find a difference in risk of bias from sequence generation, allocation concealment, follow-up and selective outcome reporting. However, industry sponsored studies more often had low risk of bias from blinding, RR: 1.25 (95% CI: 1.05 to 1.50) (13 papers), compared with non-industry sponsored studies. In industry sponsored studies, there was less agreement between the results and the conclusions than in non-industry sponsored studies, RR: 0.83 (95% CI: 0.70 to 0.98) (six papers).

AUTHORS' CONCLUSIONS

Sponsorship of drug and device studies by the manufacturing company leads to more favorable efficacy results and conclusions than sponsorship by other sources. Our analyses suggest the existence of an industry bias that cannot be explained by standard 'Risk of bias' assessments.

Defining Priorities for Future Research: Results of the UK Kidney Transplant Priority Setting Partnership

BACKGROUND

It has been suggested that the research priorities of those funding and performing research in transplantation may differ from those of end service users such as patients, carers and healthcare professionals involved in day-to-day care. The Kidney Transplant Priority Setting Partnership (PSP) was established with the aim of involving all stakeholders in prioritising future research in the field.

METHODS

The PSP methodology is as outlined by the James Lind Alliance. An initial survey collected unanswered research questions from patients, carers and clinicians. Duplicate and out-of-scope topics were excluded and the existing literature searched to identify topics answered by current evidence. An interim prioritisation survey asked patients and professionals to score the importance of the remaining questions to create a ranked long-list. These were considered at a final consensus workshop using a modified nominal group technique to agree a final top ten.

RESULTS

The initial survey identified 497 questions from 183 respondents, covering all aspects of transplantation from assessment through to long-term follow-up. These were grouped into 90 unanswered "indicative" questions. The interim prioritisation survey received 256 responses (34.8% patients/carers, 10.9% donors and 54.3% professionals), resulting in a ranked list of 25 questions that were considered during the final workshop. Participants agreed a top ten priorities for future research that included optimisation of immunosuppression (improved monitoring, choice of regimen, personalisation), prevention of sensitisation and transplanting the sensitised patient, management of antibody-mediated rejection, long-term risks to live donors, methods of organ preservation, induction of tolerance and bioengineering of organs. There was evidence that patient and carer involvement had a significant impact on shaping the final priorities.

CONCLUSIONS

The final list of priorities relates to all stages of the transplant process, including access to transplantation, living donation, organ preservation, post-transplant care and management of the failing transplant. This list of priorities will provide an invaluable resource for researchers and funders to direct future activity.

Quality and consistency of outcome reporting in clinical trials of immunosuppression in renal transplantation

Interpretation, comparison, and combination of results of clinical trials are reliant on accurate and complete reporting of outcomes. This study aimed to assess the quality and variability in outcome reporting in immunosuppression trials following renal transplantation. All randomized controlled trials comparing immunosuppressive interventions in renal transplant recipients published over a 5-year period were included. Outcomes reported in these studies were extracted, along with data regarding completeness of reporting and whether a clear definition of the method used to measure the outcome was provided. A total of 4760 outcomes were identified from 182 studies. Overall, 90.3% outcomes were completely reported; the remainder had missing data that would preclude use in meta-analysis; 31.5% manuscripts did not define a primary endpoint. Efficacy outcomes were more likely to be clearly defined than safety outcomes (OR: 0.022, P<.001) or patient-reported outcome measures (PROMs) (OR: 0.014, P<.001). PROMs were reported in less than half of manuscripts, and only five reported quality-of-life data using a validated tool. There was significant variability in the way that common efficacy and safety outcomes were defined. Variability in the way that endpoints are selected and reported in trials in renal transplantation makes interpretation and comparison between studies difficult.

Trial design and endpoints in clinical transplant research

The number of clinical trials in solid organ transplantation is progressively increasing year on year, but the quality of design and reporting still varies considerably. The constraints on organ availability, improving short-term outcomes, ethics and timescales involved in organ transplantation present unique challenges for trials in this field. An understanding of the methodology and potential pitfalls in clinical research is essential both to interpret trial results and to design robust studies. This review summarizes the scope and quality of reporting in existing transplant clinical trials and details aspects of clinical trial methodology with particular relevance to transplantation. We highlight initiatives designed to improve the quality of this process to ensure that the results of clinical trials are robust, well reported and of use in everyday clinical practice.

Reporting of intention-to-treat analyses in recent analgesic clinical trials: ACTTION systematic review and recommendations

The intention-to-treat (ITT) principle states that all subjects in a randomized clinical trial (RCT) should be analyzed in the group to which they were assigned, regardless of compliance with assigned treatment. Analyses performed according to the ITT principle preserve the benefits of randomization and are recommended by regulators and statisticians for analyses of RCTs. The objective of this study was to determine the frequency with which publications of analgesic RCTs in 3 major pain journals report an ITT analysis and the percentage of the author-declared ITT analyses that include all randomized subjects and thereby fulfill the most common interpretation of the ITT principle. RCTs investigating noninvasive, pharmacologic and interventional (eg, nerve blocks, implantable pumps, spinal cord stimulators, surgery) treatments for pain, published between January 2006 and June 2013 (n=173), were included. None of the trials using experimental pain models reported an ITT analysis; 47% of trials investigating clinical pain conditions reported an ITT analysis, and 5% reported a modified ITT analysis. Of the analyses reported as ITT, 67% reported reasons for excluding subjects from the analysis, and 18% of those listing reasons for exclusion did not do so in the Methods section. Such mislabeling can make it difficult to identify traditional ITT analyses for inclusion in meta-analyses. We hope that deficiencies in reporting identified in this study will encourage authors, reviewers, and editors to promote more consistent use of the term "intention to treat" for more accurate reporting of RCT-based evidence for pain treatments.

Exercise training in solid organ transplant recipients: a systematic review and meta-analysis

BACKGROUND

Exercise training is effective in improving the cardiovascular risk profiles of nontransplanted patients, but the health benefits and potential harms of routine exercise training after solid organ transplantation are unclear. This study aims to assess the health benefits and harms of supervised exercise training programs in solid organ recipients.

METHODS

We systematically reviewed all randomized controlled trials (RCTs) comparing the outcomes of exercise training programs in solid organ recipients against standard care. MEDLINE, EMBASE, the Transplant Library from the Centre for Evidence in Transplantation, and the Cochrane Central Register of Controlled Trials were searched to June 2012.

RESULTS

In total, 15 eligible RCTs involving 643 patients (9 cardiac transplants [n=250 patients], 2 kidney transplants [n=164 patients], 3 lung transplants [n=110 patients], and 1 liver transplant [n=119 patients]) were included. Cardiac transplant recipients who engaged in an exercise program after transplantation showed significant improvement in maximal oxygen uptake (standardized mean difference, 0.77; 95% confidence interval, 0.10-1.45) but no improvement in the overall serum lipid profile, blood pressure, and glycemic control compared with standard care. Among other solid organ transplant recipients, no significant improvements in exercise capacity or cardiovascular risk factors such as incidence of new-onset diabetes after transplantation were observed, but all effect estimates were very imprecise.

CONCLUSIONS

Exercise training is a promising but unproven intervention for improving the cardiovascular outcomes of solid organ transplant recipients. Existing trials are small, of relatively short duration, and focused on surrogate outcomes. Large-scale RCTs are urgently required if resources are to be directed toward exercise programs.

Is cytomegalovirus prophylaxis dispensable in patients receiving an mTOR inhibitor-based immunosuppression? a systematic review and meta-analysis

BACKGROUND

Cytomegalovirus (CMV) is a common opportunistic infection after solid organ transplantation. Cytomegalovirus causes increased morbidity, mortality, and reduced allograft survival. Prophylaxis may help control the virus but is associated with substantial side effects and does not completely prevent virus reactivation; relapses after cessation of the prophylaxis are frequent. Experimental and clinical data suggest that mTOR inhibitors may have an anti-CMV effect. Here, we present a meta-analysis of clinical trials after solid organ transplantation and describe potential mechanisms involved in the anti-CMV effect of mTOR-inhibitors.

METHODS

The current literature was reviewed for randomized controlled trials in solid organ transplantation comparing an mTOR-I with a non-mTOR-I (CNI based) treatment. The scientific quality of the trials was assessed by the Jadad score, the use of an effective allocation concealment (AC) and the existence of an intention-to-treat (ITT) analysis. Cytomegalovirus incidence was assessed in studies comparing 1) an mTOR-I-based with a CNI-based immunosuppression (10 trials, n=3,100 patients) and 2) an mTOR-I/CNI combination therapy with a CNI-based immunosuppression (15 trials, n=7,100 patients).

RESULTS

In the first meta-analysis, CMV events after solid organ transplantation occurred significantly more often under CNIs (RR=2.27). The second meta-analysis comparing the mTOR-I + CNI combination with a CNI treatment in 15 trials of kidney, heart, and liver transplantation showed again a higher CMV incidence when patients received an mTOR-I free immunosuppression (RR=2.45).

CONCLUSIONS

mTOR-inhibitor treatment either alone or in combination with CNIs reduces significantly the CMV incidence after organ transplantation. With the use of an mTOR-inhibitor, CMV prophylaxis may be dispensible.

Compliance to the CONSORT statement of randomized controlled trials in solid organ transplantation: a 3-year overview

The Consolidated Standards of Reporting Trials (CONSORT) statement was developed to improve the reporting quality of randomized controlled trials (RCTs). Our primary aim was to assess to what extent reports of RCTs in solid organ transplantation adhere to the 2010 CONSORT statement. Secondly, we investigated the relationship between CONSORT adherence, methodological quality and some other factors. We included 290 RCTs that were published between 2007 and 2009. We examined to what extent trial reports complied with 30 items of the CONSORT statement. Methodological quality was evaluated using the Jadad scale plus allocation concealment and whether data analysis was by randomized group (intention to treat). On average, trial reports addressed 47% of the CONSORT items. Forty-three per cent of RCTs was considered to be of good quality according to Jadad scale, and the items allocation concealment and data analysis were satisfied in approximately one-third of trials. Good quality RCTs reported on more CONSORT items than poor quality trials. The methodological quality and adherence to the CONSORT statement of RCTs published in journals that endorse the CONSORT statement was superior to those in journals without CONSORT endorsement. Overall compliance with the CONSORT statement and the methodological quality of RCTs in organ transplantation remains unsatisfactory.

Industry sponsorship and research outcome

BACKGROUND

Clinical research affecting how doctors practice medicine is increasingly sponsored by companies that make drugs and medical devices. Previous systematic reviews have found that pharmaceutical industry sponsored studies are more often favorable to the sponsor's product compared with studies with other sources of sponsorship. This review is an update using more stringent methodology and also investigating sponsorship of device studies.

OBJECTIVES

To investigate whether industry sponsored drug and device studies have more favorable outcomes and differ in risk of bias, compared with studies having other sources of sponsorship.

SEARCH METHODS

We searched MEDLINE (1948 to September 2010), EMBASE (1980 to September 2010), the Cochrane Methodology Register (Issue 4, 2010) and Web of Science (August 2011). In addition, we searched reference lists of included papers, previous systematic reviews and author files.

SELECTION CRITERIA

Cross-sectional studies, cohort studies, systematic reviews and meta-analyses that quantitatively compared primary research studies of drugs or medical devices sponsored by industry with studies with other sources of sponsorship. We had no language restrictions.

DATA COLLECTION AND ANALYSIS

Two assessors identified potentially relevant papers, and a decision about final inclusion was made by all authors. Two assessors extracted data, and we contacted authors of included papers for additional unpublished data. Outcomes included favorable results, favorable conclusions, effect size, risk of bias and whether the conclusions agreed with the study results. Two assessors assessed risk of bias of included papers. We calculated pooled risk ratios (RR) for dichotomous data (with 95% confidence intervals).

MAIN RESULTS

Forty-eight papers were included. Industry sponsored studies more often had favorable efficacy results, risk ratio (RR): 1.24 (95% confidence interval (CI): 1.14 to 1.35), harms results RR: 1.87 (95% CI: 1.54 to 2.27) and conclusions RR: 1.31 (95% CI: 1.20 to 1.44) compared with non-industry sponsored studies. Ten papers reported on sponsorship and effect size, but could not be pooled due to differences in their reporting of data. The results were heterogeneous; five papers found larger effect sizes in industry sponsored studies compared with non-industry sponsored studies and five papers did not find a difference in effect size. Only two papers (including 120 device studies) reported separate data for devices and we did not find a difference between drug and device studies on the association between sponsorship and conclusions (test for interaction, P = 0.23). Comparing industry and non-industry sponsored studies, we did not find a difference in risk of bias from sequence generation, allocation concealment and follow-up. However, industry sponsored studies more often had low risk of bias from blinding, RR: 1.32 (95% CI: 1.05 to 1.65), compared with non-industry sponsored studies. In industry sponsored studies, there was less agreement between the results and the conclusions than in non-industry sponsored studies, RR: 0.84 (95% CI: 0.70 to 1.01).

AUTHORS' CONCLUSIONS

Sponsorship of drug and device studies by the manufacturing company leads to more favorable results and conclusions than sponsorship by other sources. Our analyses suggest the existence of an industry bias that cannot be explained by standard 'Risk of bias' assessments.

Do wound complications or lymphoceles occur more often in solid organ transplant recipients on mTOR inhibitors? A systematic review of randomized controlled trials

mTOR inhibitors have been associated with wound complications and lymphoceles. We systematically reviewed randomized controlled trials (RCTs) to compare these outcomes for solid organ transplant recipients. Relevant medical databases were searched to identify RCTs in solid organ transplantation comparing mTOR inhibitors with an alternative therapy reporting on wound complications and/or lymphoceles. Methodological quality of RCTs was assessed. Pooled analyses were performed to calculate odds ratios (OR) and 95% confidence intervals (CI). Thirty-seven RCTs in kidney, heart, simultaneous pancreas-kidney and liver transplantation were included. Pooled analyses showed a higher incidence of wound complications (OR 1.77, CI 1.31-2.37) and lymphoceles (OR 2.07, CI 1.62-2.65) for kidney transplant recipients on mTOR inhibitors together with calcineurin inhibitors (CNIs). There was also a higher incidence of wound complications (OR 3.00, CI 1.61-5.59) and lymphoceles (OR 2.13, CI 1.57-2.90) for kidney transplant recipients on mTOR inhibitors together with antimetabolites. Heart transplant patients receiving mTOR inhibitors together with CNIs also reported more wound complications (OR 1.82, CI 1.15-2.87). We found a higher incidence of wound complications and lymphoceles after kidney transplantation and a higher incidence of wound complications after heart transplantation for immunosuppressive regimens that included mTOR inhibitors from the time of transplantation.