Timing and completeness of trial results posted at ClinicalTrials.gov and published in journals

Supporting study registration to reduce research waste

An estimated 82-89% of ecological research and 85% of medical research has limited or no value to the end user because of various inefficiencies. We argue that registration and registered reports can enhance the quality and impact of ecological research. Drawing on evidence from other fields, chiefly medicine, we support our claim that registration can reduce research waste. However, increasing registration rates, quality and impact will be very slow without coordinated effort of funders, publishers and research institutions. We therefore call on them to facilitate the adoption of registration by providing adequate support. We outline several aspects to be considered when designing a registration system that would best serve the field of ecology. To further inform the development of such a system, we call for more research to identify the causes of low registration rates in ecology. We suggest short- and long-term actions to bolster registration and reduce research waste.

Enhancing reporting through structure: a before and after study on the effectiveness of SPIRIT-based templates to improve the completeness of reporting of randomized controlled trial protocols

BACKGROUND

Despite the improvements in the completeness of reporting of randomized trial protocols after the publication of the Standard Protocol Items: Recommendations for Interventional Trial (SPIRIT) guidelines, many items remain poorly reported. This study aimed to assess the effectiveness of using SPIRIT-tailored templates for trial protocols to improve the completeness of reporting of the protocols that master's students write as part of their master's theses.

METHODS

Before and after experimental study performed at the University Master's Degree in Orthopaedic Manual Physiotherapy of the Universitat Internacional de Catalunya (Barcelona, Spain). While students in the post-intervention period were instructed to use a trial protocol template that was tailored to SPIRIT, students in the pre-intervention period did not use the template.

PRIMARY OUTCOME

Difference between the pre- and post-intervention periods in the mean number of adequately reported items (0-10 scale). The outcomes were evaluated independently and in duplicate by two blinded assessors. Students and their supervisors were not aware that they were part of a research project. For the statistical analysis, we used a generalized linear regression model (dependent variable: number of adequately reported items in the protocol; independent variables: intervention period, call, language).

RESULTS

Thirty-four trial protocols were included (17, pre-intervention; 17, post-intervention). Protocols produced during the post-intervention period (mean: 8.24; SD: 1.52) were more completely reported than those produced during the pre-intervention period (mean: 6.35; SD: 1.80); adjusted difference: 1.79 (95% CI: 0.58 to 3.00).

CONCLUSIONS

SPIRIT-based templates could be used to improve the completeness of reporting of randomized trial protocols.

Reporting of interventional clinical trial results in an academic center: a survey of completed studies

BACKGROUND

The dissemination of clinical trial results is an important scientific and ethical endeavour. This survey of completed interventional studies in a French academic center describes their reporting status.

METHODS

We explored all interventional studies sponsored by Rennes University Hospital identified on the French Open Science Monitor which tracks trials registered on EUCTR or clinicaltrials.gov, and provides an automatic assessment of the reporting of results. For each study, we ascertained the actual reporting of results using systematic searches on the hospital internal database, bibliographic databases (Google Scholar, PubMed), and by contacting all principal investigators (PIs). We describe several features (including total budget and numbers of trial participants) of the studies that did not report any results.

RESULTS

The French Open Science Monitor identified 93 interventional studies, among which 10 (11%) reported results. In contrast, our survey identified 36 studies (39%) reporting primary analysis results and an additional 18 (19%) reporting results for secondary analyses (without results for their primary analysis). The overall budget for studies that did not report any results was estimated to be €5,051,253 for a total of 6,735 trial participants. The most frequent reasons for the absence of results reported by PIs were lack of time for 18 (42%), and logistic difficulties (e.g. delay in obtaining results or another blocking factor) for 12 (28%). An association was found between non-publication and negative results (adjusted Odds Ratio = 4.70, 95% Confidence Interval [1.67;14.11]).

CONCLUSIONS

Even allowing for the fact that automatic searches underestimate the number of studies with published results, the level of reporting was disappointingly low. This amounts to a waste of trial participants' implication and money. Corrective actions are needed.

TRIAL REGISTRATION

https://osf.io/q5hcs.

Positive Outcome Bias in the Influential Otolaryngology Clinical Trial Literature

OBJECTIVE

To assess for the presence of positive outcome bias in the otolaryngology clinical trial literature. Specifically, we investigate the prevalence of clinical trials with positive findings (CTP) and clinical trials with negative findings (CTN), as well as their quality of evidence and subsequent impact.

STUDY DESIGN

Retrospective analysis.

SETTING

Clinical Trials in the Influential Otolaryngology Literature.

METHODS

We reviewed all clinical trials published in 4 major otolaryngology journals between 2000 and 2020. We constructed several multivariable regression models to investigate the relationship of finding direction with randomization status and citation count. Subsequently, we incorporated an interaction term between year and the primary covariate of each model to assess the temporal trajectory of these relationships. All models accounted for sample size, journal, subspecialty, and the affiliated program prestige.

RESULTS

Of the 1367 trials analyzed, 1143 (84%) were CTPs, a rate that persisted throughout the study period (aOR 1.00, 95% CI 0.98-1.03). CTPs were significantly less likely to be randomized compared to CTNs (aOR 0.25, 0.17-0.37), a relationship that persisted over time (aOR 1.05, 0.99-1.03). CTPs received significantly more citations compared to CTNs (aIRR 1.41, 1.25-1.60), a disparity that also persisted over time (aIRR 0.99, 0.97-1.01).

CONCLUSION

The otolaryngology clinical trial literature has been heavily dominated by positive findings. CTPs were more frequently cited and published even with a lower level of evidence compared to CTNs. This bias may influence the objectivity of evidence used to guide clinical practice and warrants attention when reviewing findings and changing practices.

Availability of results of clinical trials registered on EU Clinical Trials Register: cross sectional audit study

Objective

To identify the availability of results for trials registered on the European Union Clinical Trials Register (EUCTR) compared with other dissemination routes to understand its value as a results repository.

Design

Cross sectional audit study.

Setting

EUCTR protocols and results sections, data extracted 1-3 December 2020.

Population

Random sample of 500 trials registered on EUCTR with a completion date of more than two years from the beginning of searches (ie, 1 December 2018).

Main outcome measures

Proportion of trials with results across the examined dissemination routes (EUCTR, ClinicalTrials.gov, ISRCTN registry, and journal publications), and for each dissemination route individually. Prespecified secondary outcomes were number and proportion of unique results, and the timing of results, for each dissemination route.

Results

In the sample of 500 trials, availability of results on EUCTR (53.2%, 95% confidence interval 48.8% to 57.6%) was similar to the peer reviewed literature (58.6%, 54.3% to 62.9%) and exceeded the proportion of results available on other registries with matched records. Among the 383 trials with any results, 55 (14.4%, 10.9% to 17.9%) were only available on EUCTR. Also, after the launch of the EUCTR results database, median time to results was fastest on EUCTR (1142 days, 95% confidence interval 812 to 1492), comparable with journal publications (1226 days, 1074 to 1551), and exceeding ClinicalTrials.gov (3321 days, 1653 to undefined). For 117 trials (23.4%, 19.7% to 27.1%), however, results were published elsewhere but not submitted to the EUCTR registry, and no results were located in any dissemination route for 117 trials (23.4%, 19.7% to 27.1).

Conclusions

EUCTR should be considered in results searches for systematic reviews and can help researchers and the public to access the results of clinical trials, unavailable elsewhere, in a timely way. Reporting requirements, such as the EU's, can help in avoiding research waste by ensuring results are reported. The registry's true value, however, is unrealised because of inadequate compliance with EU guidelines, and problems with data quality that complicate the routine use of the registry. As the EU transitions to a new registry, continuing to emphasise the importance of EUCTR and the provision of timely and complete data is critical. For the future, EUCTR will still hold important information from the past two decades of clinical research in Europe. With increased efforts from sponsors and regulators, the registry can continue to grow as a source of results of clinical trials, many of which might be unavailable from other dissemination routes.

A Novel Method for Deriving Adverse Event Prevalence in Randomized Controlled Trials: Potential for Improved Understanding of Benefit-Risk Ratio and Application to Drug Labels

INTRODUCTION

Adverse event (AE) data in randomized controlled trials (RCTs) allow quantification of a drug's safety risk relative to placebo and comparison across medications. The standard US label for Food and Drug Administration-approved drugs typically lists AEs by MedDRA Preferred Term that occur at ≥ 2% in drug and with greater incidence than in placebo. We suggest that the drug label can be more informative for both patients and physicians if it includes, in addition to AE incidence (percent of subjects who reported the AE out of the total subjects in treatment), the absolute prevalence (percent of subject-days spent with an AE out of the total subject-days spent in treatment) and expected duration (days required for AE incidence to be reduced by half). We also propose a new method to analyze AEs in RCTs using drug-placebo difference in AE prevalence to improve safety signal detection.

METHODS

AE data from six RCTs in schizophrenia were analyzed (five RCTs of the dopamine D2 receptor-based antipsychotic lurasidone and one RCT of the novel trace amine-associated receptor 1 [TAAR1] agonist ulotaront). We determined incidence, absolute prevalence, and expected duration of AEs for lurasidone and ulotaront vs respective placebo. We also calculated areas under the curve of drug-placebo difference in AE prevalence and mean percent contribution of each AE to this difference.

RESULTS

A number of AEs with the same incidence had different absolute prevalence and expected duration. When accounting for these two parameters, AEs that did not appear in the 2% incidence tables of the drug label turned out to contribute substantially to drug tolerability. The percent contribution of a drug-related AE to the overall side effect burden increased the drug-placebo difference in AE prevalence, whereas the percent contribution of a placebo-related AE decreased such difference, revealing a continuum of risk between drug and placebo. AE prevalence curves for drug were generally greater than those for placebo. Ulotaront exhibited a small drug-placebo difference in AE prevalence curves due to a relatively low incidence and short duration of AEs in the ulotaront treatment arm as well as the emergence of disease-related AEs in the placebo arm.

CONCLUSION

Reporting AE absolute prevalence and expected duration for each RCT and incorporating them in the drug label is possible, is clinically relevant, and allows standardized comparison of medications. Our new metric, the drug-placebo difference in AE prevalence, facilitates signal detection in RCTs. We piloted this metric in RCTs of several neuropsychiatric indications and drugs, offering a new way to compare AE burden and tolerability among treatments using existing clinical trial information.

The Relative Age Effect at Different Age Periods in Soccer: A Meta-Analysis

In the selection of young athletes, earlier-born adolescents often leverage their temporary biological advantage over their later-born peers from the same cohort, giving rise to the phenomenon known as the Relative Age Effect (RAE). In this study, we delved into the complexities of the RAE in soccer by reviewing 563 independent research samples across 90 articles. Our analysis showed that age period and performance level are pivotal factors influencing the magnitude of the RAE. The adolescent age period emerged as a significant RAE determinant, showcasing the highest effect size magnitudes in our findings. Among athletes of different performance levels, adult European soccer players have been extensively studied, and they have exhibited the most pronounced RAE magnitudes. Intriguingly, our findings reveal another compelling trend: the frequency of players born early versus late in the eligible birth year escalated as player performance levels increased, particularly during adolescence. Coaches and players appear to capitalize unconsciously on this maturational advantage, though this strategy wanes post-adolescence. While there are currently no penalties for this team selection practice, our findings stress the need for coaches to comprehend the ramifications of selecting athletes with an age bias We offer insights into RAE complexities, highlight the synergy of age and performance in these transitory advantages, and advance arguments for more fairly selecting and developing youth athletes.

Dissemination of Registered COVID-19 Clinical Trials (DIRECCT): a cross-sectional study

BACKGROUND

The results of clinical trials should be completely and rapidly reported during public health emergencies such as COVID-19. This study aimed to examine when, and where, the results of COVID-19 clinical trials were disseminated throughout the first 18 months of the pandemic.

METHODS

Clinical trials for COVID-19 treatment or prevention were identified from the WHO ICTRP database. All interventional trials with a registered completion date ≤ 30 June 2021 were included. Trial results, published as preprints, journal articles, or registry results, were located using automated and manual techniques across PubMed, Google Scholar, Google, EuropePMC, CORD-19, the Cochrane COVID-19 Study Register, and clinical trial registries. Our main analysis reports the rate of dissemination overall and per route, and the time from registered completion to results using Kaplan-Meier methods, with additional subgroup and sensitivity analyses reported.

RESULTS

Overall, 1643 trials with completion dates ranging from 46 to 561 days prior to the start of results searches were included. The cumulative probability of reporting was 12.5% at 3 months from completion, 21.6% at 6 months, and 32.8% at 12 months. Trial results were most commonly disseminated in journals (n = 278 trials, 69.2%); preprints were available for 194 trials (48.3%), 86 (44.3%) of which converted to a full journal article. Trials completed earlier in the pandemic were reported more rapidly than those later in the pandemic, and those involving ivermectin were more rapidly reported than other common interventions. Results were robust to various sensitivity analyses except when considering only trials in a "completed" status on the registry, which substantially increased reporting rates. Poor trial registry data on completion status and dates limits the precision of estimates.

CONCLUSIONS

COVID-19 trials saw marginal increases in reporting rates compared to standard practice; most registered trials failed to meet even the 12-month non-pandemic standard. Preprints were common, complementing journal publication; however, registries were underutilized for rapid reporting. Maintaining registry data enables accurate representation of clinical research; failing to do so undermines these registries' use for public accountability and analysis. Addressing rapid reporting and registry data quality must be emphasized at global, national, and institutional levels.

Reasons for missing evidence in rehabilitation meta-analyses: a cross-sectional meta-research study

BACKGROUND

Systematic reviews of randomized controlled trials are the best evidence for informing on intervention effectiveness. Their results, however, can be biased due to omitted evidence in the quantitative analyses. We aimed to assess the proportion of randomized controlled trials omitted from meta-analyses in the rehabilitation field and explore related reasons.

METHODS

This is a cross-sectional meta-research study. For each systematic review included in a published selected sample in the rehabilitation field, we identified an index meta-analysis on the primary outcome and the main comparison. We then looked at all the studies considered eligible for the chosen comparison in the systematic review and identified those trials that have been omitted (i.e., not included) from each index meta-analysis. Reasons for omission were collected based on an eight-reason classification. We used descriptive statistics to describe the proportion of omitted trials overall and according to each reason.

RESULTS

Starting from a cohort of 827 systematic reviews, 131 index meta-analyses comprising a total of 1761 eligible trials were selected. Only 16 index meta-analyses included all eligible studies while 15 omitted studies without providing references. From the remaining 100 index meta-analyses, 717 trials (40,7%) were omitted overall. Specific reasons for omission were: "unable to distinguish between selective reporting and inadequate planning" (39,3%, N = 282), "inadequate planning" (17%, N = 122), "justified to be not included" (15,1%, N = 108), "incomplete reporting" (8,4%, N = 60), "selective reporting" (3,3%, N = 24) and other situations (e.g., outcome present but no motivation for omission) (5,2%, N = 37). The 11,7% (N = 84) of omitted trials were not assessed due to non-English language or full text not available.

CONCLUSIONS

Almost half of the eligible trials were omitted from their index meta-analyses. Better reporting, protocol registration, definition and adoption of core outcome sets are needed to prevent omission of evidence in systematic reviews.

Chinese Clinical Trial Registry 13-year data collection and analysis: geographic distribution, financial support, research phase, duration, and disease categories

Objective

To evaluate the current status of trial registration on the Chinese Clinical Trial Registry (ChiCTR).

Design

In this descriptive study, a multi-dimensional grouping analysis was conducted to estimate trends in the annual trial registration, geographical distribution, sources of funding, targeted diseases, and trial subtypes.

Setting

We have analyzed all clinical trial records (over 30,000) registered on the Chinese Clinical Trial Registry (ChiCTR) from 2007 to 2020 executed in China.

Main outcomes and measures

The main outcome was the baseline characteristics of registered trials. These trials were categorized and analyzed based on geographical distribution, year of implementation, disease type, resource and funding type, trial duration, trial phase, and the type of experimental approach.

Results

From 2008 to 2017, a consistent upward trend in clinical trial registrations was observed, showing an average annual growth rate of 29.2%. The most significant year-on-year (yoy%) growth in registrations occurred in 2014 (62%) and 2018 (68.5%). Public funding represented the predominant source of funding in the Chinese healthcare system. The top five ChiCTR registration sites for all disease types were highly populated urban regions of China, including Shanghai (5,658 trials, 18%), Beijing (5,127 trials, 16%), Guangdong (3,612 trials, 11%), Sichuan (2,448 trials, 8%), and Jiangsu (2,196 trials, 7%). Trials targeting neoplastic diseases accounted for the largest portion of registrations, followed by cardio/cerebrovascular disease (CCVD) and orthopedic diseases-related trials. The largest proportions of registration trial duration were 1-2 years, less than 1 year, and 2-3 years (at 27.36, 26.71, and 22.46%). In the case of the research phase, the top three types of all the registered trials are exploratory research, post-marketing drugs, and clinical trials of new therapeutic technology.

Conclusion and relevance

Oncological and cardiovascular diseases receive the highest share of national public funding for medical clinical trial-based research in China. Publicly funded trials represent a major segment of the ChiCTR registry, indicating the dominating role of public governance in this health research sector. Furthermore, the growing number of analyzed records reflect the escalation of clinical research activities in China. The tendency to distribute funding resources toward exceedingly populated areas with the highest incidence of oncological and cardiovascular diseases reveals an aim to reduce the dominating disease burden in the urban conglomerates in China.

Quality of reporting of adverse events in clinical trials of covid-19 drugs: systematic review

Objective

To assess the quality of reporting of adverse events in clinical trials of covid-19 drugs based on the CONSORT (Consolidated Standards of Reporting Trials) harms extension and according to clinical trial design, and to examine reporting of serious adverse events in drug trials published on PubMed versus clinical trial summaries on ClinicalTrials.gov.

Design

Systematic review.

Data sources

PubMed and ClinicalTrials.gov registries were searched from 1 December 2019 to 17 February 2022.

Eligibility criteria for selecting studies

Randomised clinical trials evaluating the efficacy and safety of drugs used to treat covid-19 disease in participants of all ages with suspected, probable, or confirmed SARS-CoV-2 infection were included. Clinical trials were screened on title, abstract, and text by two authors independently. Only articles published in French and English were selected. The Cochrane risk of bias tool for randomised trials (RoB 2) was used to assess risk of bias.

Results

The search strategy identified 1962 randomised clinical trials assessing the efficacy and safety of drugs used to treat covid-19, published in the PubMed database; 1906 articles were excluded after screening and 56 clinical trials were included in the review. Among the 56 clinical trials, no study had a high score for quality of reporting of adverse events, 60.7% had a moderate score, 33.9% had a low score, and 5.4% had a very low score. All clinical trials with a very low score for quality of reporting of adverse events were randomised open label trials. For reporting of serious adverse events, journal articles published on PubMed under-reported 51% of serious adverse events compared with clinical trial summaries published on ClinicalTrials.gov.

Conclusions

In one in three published clinical trials on covid-19 drugs, the quality of reporting of adverse events was low or very low. Differences were found in the number of serious adverse events reported in journal articles versus clinical trial summaries. During the covid-19 pandemic, risk assessment of drugs in clinical trials of covid-19 drugs did not comply with good practice recommendations for publication of results.

Systematic review registration

European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP) EUPAS45959.

Reporting characteristics of nonsurgical periodontal therapy trials registered in ClinicalTrials.gov: an observational study

Aim: To evaluate the completeness of the description of nonsurgical periodontal therapy interventions in clinical trials registered in ClinicalTrials.gov and correspondence of registered information for trial participants and outcome measures with published articles. Materials & methods: We retrieved data from ClinicalTrials.gov and corresponding publications. The completeness of intervention reporting was assessed using the Template for Intervention Description and Replication (TIDieR) checklist for oral hygiene instructions (OHI), professional mechanical plaque removal (PMPR), and subgingival instrumentation, antiseptics and antibiotics. The completeness of registration of trial protocol information was assessed according to the WHO Trial Registration DataSet for participant information (enrollment, sample size calculation, age, gender, condition) and primary/secondary outcome measures. Results: 79 included trials involved OHI (n = 38 trials, 48.1%), PMPR (n = 19, 24.1%), antiseptics (n = 11, 12.7%), or antibiotics (n = 11, 12.7%). There was a great variety in the terms used to describe these interventions. Most of the analyzed trials (93.7%) were completed and did not provide any data on study phase (74.7%). The description of intervention in the registry in ClinicalTrials.gov was inadequate for all analyzed interventions, with description inconsistencies in matching publications. There were also discrepancies in registered and published outcomes: for 39 trials with published results, 18 had different registered and reported primary outcomes, and 29 different registered and reported secondary outcomes. Conclusion: The completeness of the description of nonsurgical therapy of periodontitis in clinical trials is unsatisfactory, reducing the quality of translation of the new evidence and procedures into clinical practice. Significant discrepancy in registered and reported trial outcomes calls into question the validity of reported results and relevance for practice.

A Pilot Study on Result Reporting Rates from Clinical Trials of Regenerative Medicine

Sharing the methods and results of clinical trials with full transparency is an ethical obligation for those involved in clinical research. In this regard, ClinicalTrials.gov requires reporting of results to the registry within 1 year of completion of the trial. However, a poor result reporting rate has been pointed out, with approximately half the trial results not been reported. It has been suggested that one of the reasons behind this could be the influence of sponsors who conduct the clinical trials. In the course of our previous trend analysis on regenerative medicine for stroke (STR) using ClinicalTrials.gov and the International Clinical Trials Registry Platform (ICTRP) portal site as data sources, we suspected whether the results of gene and/or cell therapy trials are poorly reported. For this reason, a multivariate analysis using data from ClinicalTrials.gov was performed to identify the factors suppressing the result reporting rate, expanding our study to four different kinds of neurological diseases and regenerative medicine as a treatment modality when small-molecule compounds and biologics were set up as controls, in addition to the sponsor type factor. As a result, we found gene and/or cell therapy (therapeutic modality) in addition to STR (disease area), trials completed in 2005-2007, and clinical phases II and IV as independent factors that suppressed the rate of reporting results to ClinicalTrials.gov. On the other hand, big pharmaceutical companies were identified as a factor that increased the reporting result rate to ClinicalTrials.gov. When we applied result reporting publications through PubMed as an index, our study data revealed that the following factors were not identified as the cause for a decrease in the reporting result rate: STR (as disease area), trials completed between 2005 and 2007, and gene/cell therapy (as treatment modality). In this context, our findings indicate that gene/cell therapy has led to the suppression of the result reporting rate to ClinicalTrials.gov. This confirmed our initial suspicion of the low result reporting rate of gene/cell therapy trials. We believe that further studies are required to elucidate the factors affecting the result reporting rate from the perspective of disease area and treatment modality. Impact Statement Several studies have addressed the poor result reporting rate of clinical trials, which still remains an issue. Regenerative medicine holds great promise for the future and the process of its practical application is expected to be challenging. Although having a limited disease area and small sample size, to the best of our knowledge, this is the first study to point out insufficient result reporting of clinical trials of regenerative medicine from the perspective of treatment modality. This report highlights an issue for discussing the path toward its translation through an overview of various factors in comparison with conventional treatment modalities.

Randomised controlled trials evaluating anticancer therapies in haematological cancers: an overview of global research activity

Background

Design, results, and interpretation of oncology randomised controlled trials (RCTs) have changed substantially over the past decade. In this study, we describe all RCTs evaluating anticancer therapies in haematological cancers published globally during 2014-2017 with comparisons with solid tumours RCTs.

Methods

A PubMed literature search identified all phase 3 RCTs of anticancer therapy for haematological cancers and solid tumours published globally during 2014-2017. Descriptive statistics, chi-square tests and the Kruskal-Wallis test were used to compare RCT design results, and output between haematological cancers and solid tumours as well as for different haematological cancer subtypes.

Results

694 RCTs were identified; 124 in haematological cancers and 570 in solid tumours. Overall survival (OS) was the primary endpoint in only 12% (15/124) of haematological cancer trials compared to 35% (200/570) in solid tumours (p < 0.001). Haematological cancer RCTs evaluated the systemic novel therapy more often than the solid tumour RCT (98% versus 84%, p = 0.002). Use of surrogate endpoints like progression-free survival (PFS) and time to treatment failure (TTF) were more common in haematological cancers than solid tumours (47% versus 31%, p < 0.001). Within haematological cancers, the use of PFS and TTF was more prevalent in chronic lymphocytic leukaemia and multiple myeloma as compared to others (80%-81% versus 0%-41%, p < 0.001). Seventy-eight percent of haematologic trials were funded by industry as compared to 70% of solid tumour trials. Only 4% (5/124) of haematologicalcancer trials were led by investigators in upper-middle and lower-middle-income countries as compared to the 9% of solid tumour trials.

Conclusion

The fact that only 12% of haematological cancer RCTs are designed to show improvements in OS is of grave concern for the field and the care of future patients. This is further compounded by the highly prevalent use of alternative primary endpoints that are rarely valid surrogates for OS in haematological cancers.

Is our public research money well spent? Publication of research outputs from Health Research Council of New Zealand-funded studies: a cross-sectional study

OBJECTIVE

To evaluate the reporting of results from the projects and programmes funded by the Health Research Council (HRC) New Zealand.

DESIGN

A cross-sectional analysis.

SETTING

Research projects and programmes funded by the HRC New Zealand from 2006 to 2014.

PARTICIPANTS

Publicly available data provided by the HRC.

MAIN OUTCOME MEASURES

The number and proportion with evidence of publication and dissemination of a research output from HRC grants and the time taken to disseminate the results.

RESULTS

Of the 374 HRC grants from 2006 to 2014, there was no evidence of publication or reporting of any research output for 48 studies (13%). Of the 326 (87%) grants with research outputs, there was a mean dissemination time of 4.73 years (SD 2.37). The total funding provided by the HRC was NZ$471 663 336, while the 48 grants with no evidence of dissemination represented NZ$47 095 727 (10%).

CONCLUSIONS

Thirteen per cent of the HRC projects and programmes from 2006 to 2014 have not contributed to the healthcare evidence as their results remain unknown.

Comparison of Availability of Trial Results in ClinicalTrials.gov and PubMed by Data Source and Funder Type

This study examines the dissemination of trial results by data source (ie, ClinicalTrials.gov and PubMed) and funder type (ie, industry and nonindustry).

Consistency between trials presented at conferences, their subsequent publications and press releases

OBJECTIVE

This study examined the extent to which trials presented at major international medical conferences in 2016 consistently reported their study design, end points and results across conference abstracts, published article abstracts and press releases.

DESIGN

Cross-sectional analysis of clinical trials presented at 12 major medical conferences in the USA in 2016. Conferences were identified from a list of the largest clinical research meetings aggregated by the Healthcare Convention and Exhibitors Association and were included if their abstracts were publicly available. From these conferences, all late-breaker clinical trials were included, as well as a random selection of all other clinical trials, such that the total sample included up to 25 trial abstracts per conference.

MAIN OUTCOME MEASURES

First, it was determined if trials were registered and reported results in an International Committee of Medical Journal Editors-approved clinical trial registry. Second, it was determined if trial results were published in a peer-reviewed journal. Finally, information on trial media coverage and press releases was collected using LexisNexis. For all published trials, the consistency of reporting of the following characteristics was examined, through comparison of the trials' conference and publication abstracts: primary efficacy endpoint definition, safety endpoint identification, sample size, follow-up period, primary end point effect size and characterisation of trial results. For all published abstracts with press releases, the characterisation of trial results across conference abstracts, press releases and publications was compared. Authors determined consistency of reporting when identical information was presented across abstracts and press releases. Primary analyses were descriptive; secondary analyses included χ2 tests and multiple logistic regression.

RESULTS

Among 240 clinical trials presented at 12 major medical conferences, 208 (86.7%) were registered, 95 (39.6%) reported summary results in a registry and 177 (73.8%) were published; 82 (34.2%) were covered by the media and 68 (28.3%) had press releases. Among the 177 published trials, 171 (96.6%) reported the definition of primary efficacy endpoints consistently across conference and publication abstracts, whereas 96/128 (75.0%) consistently identified safety endpoints. There were 107/172 (62.2%) trials with consistent sample sizes across conference and publication abstracts, 101/137 (73.7%) that reported their follow-up periods consistently, 92/175 (52.6%) that described their effect sizes consistently and 157/175 (89.7%) that characterised their results consistently. Among the trials that were published and had press releases, 32/32 (100%) characterised their results consistently across conference abstracts, press releases and publication abstracts. No trial characteristics were associated with reporting primary efficacy end points consistently.

CONCLUSIONS

For clinical trials presented at major medical conferences, primary efficacy endpoint definitions were consistently reported and results were consistently characterised across conference abstracts, registry entries and publication abstracts; consistency rates were lower for sample sizes, follow-up periods, and effect size estimates.

REGISTRATION

This study was registered at the Open Science Framework (https://doi.org/10.17605/OSF.IO/VGXZY).

Atrial Fibrillation Incidence Associated With Exposure to Anticancer Drugs Used as Monotherapy in Clinical Trials

Background

The incidence of atrial fibrillation (AF) associated with anticancer drugs in cancer patients remains incompletely defined.

Objectives

The primary outcome was the annualized incidence rate of AF reporting associated with exposure to 1 of 19 anticancer drugs used as monotherapy in clinical trials. The authors also report the annualized incidence rate of AF reported in the placebo arms of these trials.

Methods

The authors systematically searched ClinicalTrials.gov for phase 2 and 3 cancer trials studying 19 different anticancer drugs of interest used as monotherapy, up to September 18, 2020. The authors performed a random-effects meta-analysis to compute summary AF annualized incidence rate with its 95% CI using log transformation and inverse variance weighting.

Results

A total of 191 clinical trials (47.1% were randomized) of 16 anticancer drugs across 26,604 patients were included. Incidence rates could be calculated for 15 drugs administered singly as monotherapy. Summary annualized incidence rates of AF reporting associated with exposure to 1 of the 15 anticancer drugs used as monotherapy were derived; these ranged from 0.26 to 4.92 per 100 person-years. The 3 highest annualized incidence rates of AF reporting were found for ibrutinib 4.92 (95% CI: 2.91-8.31), clofarabine 2.38 (95% CI: 0.66-8.55), and ponatinib 2.35 (95% CI: 1.78-3.12) per 100 person-years. Summary annualized incidence rate of AF reporting in the placebo arms was 0.25 per 100 person-years (95% CI: 0.10-0.65).

Conclusions

AF reporting is not a rare event associated with anticancer drugs in clinical trials. A systematic and standardized AF detection should be considered in oncological trials, particularly those studying anticancer drugs associated with high AF rates. (Incidence of atrial fibrillation associated with anticancer drugs exposure in monotherapy, A safety meta-analysis of phase 2 and 3 clinical trials; CRD42020223710).

E-cigarette manufacturers' compliance with clinical trial reporting expectations: a case series of registered trials by Juul Labs

BACKGROUND

Electronic cigarettes (e-cigarettes) are a frequently debated topic in public health. It is essential that clinical trials examining e-cigarettes are fully and accurately reported, especially given long-standing concerns about tobacco industry research. We assess the reporting of clinical trials sponsored by Juul Labs, the largest e-cigarette company in the USA, against accepted reporting standards.

METHODS

We searched ClinicalTrials.gov for all trials sponsored by Juul Labs and determined those with registry data consistent with coverage by the Food and Drug Administration (FDA) Amendments Act 2007 (FDAAA). For trials with a primary completion date more than 1 year earlier, we searched ClinicalTrials.gov, the academic literature and a Juul-funded research database (JLI Science) for results. For located results, we compared reported outcomes with registered outcomes in line with Consolidated Standards of Reporting Trials (CONSORT) reporting guidelines.

RESULTS

We located five registered trials sponsored by Juul Labs that appeared covered by the FDAAA 2007 in the public data. All five trials did not have results available on ClinicalTrials.gov. We found one publication and four poster presentations reporting results for four of the five covered trials outside of ClinicalTrials.gov. Of 61 specified outcomes, 28 were CONSORT compliant. Specific outcome reporting issues are detailed.

DISCUSSION

Our findings raise substantial concerns regarding these trials. Clinicians, public health professionals, and the public cannot make informed choices about the benefits or hazards of e-cigarettes if the results of clinical trials are not completely and transparently reported. Clarification and potential enforcement of reporting laws may be required.

Predicting Publication of Clinical Trials Using Structured and Unstructured Data: Model Development and Validation Study

BACKGROUND

Publication of registered clinical trials is a critical step in the timely dissemination of trial findings. However, a significant proportion of completed clinical trials are never published, motivating the need to analyze the factors behind success or failure to publish. This could inform study design, help regulatory decision-making, and improve resource allocation. It could also enhance our understanding of bias in the publication of trials and publication trends based on the research direction or strength of the findings. Although the publication of clinical trials has been addressed in several descriptive studies at an aggregate level, there is a lack of research on the predictive analysis of a trial's publishability given an individual (planned) clinical trial description.

OBJECTIVE

We aimed to conduct a study that combined structured and unstructured features relevant to publication status in a single predictive approach. Established natural language processing techniques as well as recent pretrained language models enabled us to incorporate information from the textual descriptions of clinical trials into a machine learning approach. We were particularly interested in whether and which textual features could improve the classification accuracy for publication outcomes.

METHODS

In this study, we used metadata from ClinicalTrials.gov (a registry of clinical trials) and MEDLINE (a database of academic journal articles) to build a data set of clinical trials (N=76,950) that contained the description of a registered trial and its publication outcome (27,702/76,950, 36% published and 49,248/76,950, 64% unpublished). This is the largest data set of its kind, which we released as part of this work. The publication outcome in the data set was identified from MEDLINE based on clinical trial identifiers. We carried out a descriptive analysis and predicted the publication outcome using 2 approaches: a neural network with a large domain-specific language model and a random forest classifier using a weighted bag-of-words representation of text.

RESULTS

First, our analysis of the newly created data set corroborates several findings from the existing literature regarding attributes associated with a higher publication rate. Second, a crucial observation from our predictive modeling was that the addition of textual features (eg, eligibility criteria) offers consistent improvements over using only structured data (F₁-score=0.62-0.64 vs F₁-score=0.61 without textual features). Both pretrained language models and more basic word-based representations provide high-utility text representations, with no significant empirical difference between the two.

CONCLUSIONS

Different factors affect the publication of a registered clinical trial. Our approach to predictive modeling combines heterogeneous features, both structured and unstructured. We show that methods from natural language processing can provide effective textual features to enable more accurate prediction of publication success, which has not been explored for this task previously.

Reporting of the safety from allergic rhinitis trials registered on ClinicalTrials.gov and in publications: An observational study

BACKGROUND

Incomplete and inconsistent reporting of adverse events (AEs) through multiple sources can distort impressions of the overall safety of the medical interventions examined as well as the benefit-risk relationship. We aimed to assess completed allergic rhinitis (AR) trials registered in ClinicalTrials.gov for completeness and consistency of AEs reporting comparing ClinicalTrials.gov and corresponding publications.

METHODS

We retrospectively examined completed randomised controlled trials on AR registered in ClinicalTrials.gov on or after 9/27/2009 to trials updated with results on or before 12/31/2021 along with any corresponding publications. Complete reporting of AEs in ClinicalTrials.gov were summarised in tables describing AE information, and complete reporting in publications was an explicit statement of serious AE, death or other AE. Difference in completeness, number, or description of AEs between ClinicalTrials.gov and publication was classified as inconsistent reporting of AEs.

RESULTS

There were 99 registered trials with 45 (45.5%) available publications. All published trials completely reported AEs in ClinicalTrials.gov, and 21 (46.7%) in publications (P < .001). In 43 (95.6%) publications, there was at least one inconsistency in the reporting of AEs (P < .001). 8 (17.8%) publications had different number of serious AEs (P = .003), 36 (80.0%) of other AEs (P < .001) while deaths reporting was inconsistent in 8 (57.1%) publications (P = .127).

CONCLUSION

The reporting of AEs from AR trials is complete in ClinicalTrials.gov and incomplete and inconsistent in corresponding publications. There is a need to improve the reporting of AEs from AR trials in corresponding publications, and thus to improve patient safety.

Availability of Results of Trials Studying Pancreatic Adenocarcinoma over the Past 10 Years

BACKGROUND

Pancreatic adenocarcinoma (PDAC) is a lethal cancer with few therapeutic options. Availability of results is a crucial step in interventional research. Our aim was to evaluate results availability for trials in patients with PDAC and explore associated factors.

MATERIALS AND METHODS

We performed a retrospective cohort study and searched the ClinicalTrials.gov registry for trials evaluating PDAC management with a primary completion date between 1 January 2010 and 1 June 2020. Then, we searched for results submitted on ClinicalTrials.gov and/or published. Our primary outcome was the proportion of PDAC trials with available results: submitted on ClinicalTrials.gov (either publicly available or undergoing quality control check) and/or published in a full-text article. The association of predefined trial characteristics with results availability was assessed.

RESULTS

We identified 551 trials of which 386 (70%) had available results. The cumulative percentage of trials with available results was 21% (95% CI, 18-25%) at 12 months after the primary completion date, 44% (95% CI, 30-48%) at 24 months and 57% (95% CI, 53-61%) at 36 months. Applicable clinical trials, required to comply with the 2007 Food and Drug Administration Amendments Act 801 and its final rule on reporting of results on ClinicalTrials.gov, were more likely to have available results over time (HR 2.1 [95% CI 1.72-2.63], P < .001). Industry-funded, small sample size, and terminated trials were less likely to have available results. Other trial characteristics showed no association with results availability.

CONCLUSION

Our results highlight a waste in interventional research studying PDAC.

Reporting of clinical trial safety results in ClinicalTrials.gov for FDA-approved drugs: A cross-sectional analysis

BACKGROUND

Adverse events identified during clinical trials can be important early indicators of drug safety, but complete and timely data on safety results have historically been difficult to access. The aim was to compare the availability, completeness, and concordance of safety results reported in ClinicalTrials.gov and peer-reviewed publications.

METHODS

We analyzed clinical trials used in the Food and Drug Administration safety assessment of new drugs approved between 1 July 2018 and 30 June 2019. The key safety outcomes examined were all-cause mortality, serious adverse events, adverse events, and withdrawals due to adverse events. Availability of safety results was measured by the presence and timing of a record of trial-level results in ClinicalTrials.gov and a corresponding peer-reviewed publication. For the subset of trials with available results, completeness was defined as the reporting of safety results for all participants and compared between ClinicalTrials.gov and publications. To assess concordance, we compared the numeric results for safety outcomes reported in ClinicalTrials.gov and publications to results in Food and Drug Administration trial reports.

RESULTS

Among 156 trials studying 52 drugs, 91 (58.3%) trials reported safety results in ClinicalTrials.gov and 106 (67.9%) in peer-reviewed publications (risk difference = -9.6%, 95% confidence interval = -20.3 to 1.0). All-cause mortality was reported sooner in published articles compared with ClinicalTrials.gov (log-rank test, p = 0.01). There was no difference in time to reporting for serious adverse events (p = 0.05), adverse events (p = 0.09), or withdrawals due to adverse events (p = 0.20). Complete reporting of all-cause mortality was similar in ClinicalTrials.gov and publications (74.7% vs 78.3%, respectively; risk difference = -3.6%, 95% confidence interval = -15.5 to 8.3) and higher in ClinicalTrials.gov for serious adverse events (100% vs 79.2%; risk difference = 20.8%, 95% confidence interval = 13.0 to 28.5) and adverse events (100% vs 86.8%; risk difference = 13.2%, 95% confidence interval = 6.8 to 19.7). Withdrawals due to adverse events were less often completely reported in ClinicalTrials.gov (62.6% vs 92.5%; risk difference = -29.8%, 95% confidence interval = -40.1 to -18.7). No difference was found in concordance of results between ClinicalTrials.gov and publications for all-cause mortality, serious adverse events, or withdrawals due to adverse events.

CONCLUSION

Safety results were available in ClinicalTrials.gov at a similar rate as in peer-reviewed publications, with more complete reporting of certain safety outcomes in ClinicalTrials.gov. Future efforts should consider adverse event reporting in ClinicalTrials.gov as an accessible data source for post-marketing surveillance and other evidence synthesis tasks.

Availability of results of interventional studies assessing colorectal cancer from 2013 to 2020

Colorectal cancer (CRC) is one of the most frequent cancers worldwide. Our aim was to evaluate the availability of results of interventional studies studying CRC. We searched the ClinicalTrials.gov registry for all interventional studies on CRC management in adults completed or terminated between 01/01/2013 and 01/01/2020. To identify results, we searched for results posted on the ClinicalTrials.gov registry and/or published in a full-text article. Our primary outcome was the proportion of CRC interventional studies with available results (i.e. posted on the ClinicalTrials.gov registry and/or published in a full-text article). Secondary outcomes were 1) median time between primary completion and earliest date of results availability, 2) the cumulative percentage of interventional studies with results available over time 3) the cumulative percentage of interventional studies with results posted on the ClinicalTrials.gov registry over time and 4) the percentage of results available in open access. We identified 763 eligible interventional studies in ClinicalTrials.gov, which included 679 198 patients. Of these, 286 (37%) trials, including 270 845 (40%) patients, did not have any results available. Median time for results availability was 32.6 months (IQ 16.1-unreached). The cumulative percentage of interventional studies with available results was 17% at 12 months, 39% at 24 months and 55% at 36 months. Results were more likely available for trials that were randomized, completed, had one trial site in the United States, and with mixed funding. The cumulative percentage of interventional studies with results posted on ClinicalTrials.gov was 2% at 12 months. Results were available in open access for 420 (420/477 = 88%) trials. Our results highlight an important waste in research for interventional studies studying CRC.

Trends and variation in data quality and availability on the European Union Clinical Trials Register: A cross-sectional study

BACKGROUND/AIMS

The European Union Clinical Trials Register is a public facing portal containing information on trials of medicinal products conducted under the purview of the European Union regulatory system. As of September 2021, the registry holds information on over 40,000 trials. Given its distinct regulatory purpose, and results reporting requirements, the European Union Clinical Trials Register should be a valuable open-source hub for trial information. Past work examining the European Union Clinical Trials Register has suggested that data quality on the registry may be lacking. We therefore set out to examine the quality and availability of trial data on the registry with a focus on areas that fall under the authority of regulators in each European Union/European Economic Area country.

METHODS

Using data scraped from the full European Union Clinical Trials Register public dataset, we examined the extent of issues with three areas of trial data availability linked to European Union regulations. We examined whether there is evidence for missing registration of protocols in the public database, whether information on the completion of clinical trials is being made available and how often the results of trials are posted to the registry. We assessed each area overall, and examined variation between national regulators and over time.

RESULTS

Major issues with the availability of expected protocols and information on trial completion were focused in a few countries. Overall, when comparing enrolment countries from tabular results to available registrations, 26,932 of 31,118 (86.5%) expected protocols were available and 22 of 30 (73%) countries had over 90% of expected protocols available. The majority of missing protocols, totalling 2764 (66%), were from just three countries: France, Norway and Poland. Evidence for this issue is further supported by data on trends in new registrations by country over time. Low availability of data on trial completion is also most pronounced in a minority of countries, like Spain and the Netherlands, with consistent trends for missingness over time. Finally, overall results availability is substantially worse among the 23,623 trials with a single registered European Union protocol (n = 6259, 26.5%) compared to 13,897 of those taking place in multiple countries (n = 8423, 60.6%). Reporting for single-protocol trials was consistently low across both time and location.

CONCLUSION

Deficiencies in the public availability of trial protocols, trial completion information and summary results complicate the utility of the European Union Clinical Trials Register for research, transparency and accountability efforts. Users of the registry would benefit from a more complete and accurate accounting of the European research environment via the official European Union registry. We recommend regulators at the national and pan-national level undertake routine audits of approved trials to ensure national-level issues are proactively and transparently identified, documented and addressed.

Assessment of transparency and selective reporting of interventional trials studying colorectal cancer

Background

Colorectal cancer (CRC) is currently one of the most frequently diagnosed cancers. Our aim was to evaluate transparency and selective reporting in interventional trials studying CRC.

Methods

First, we assessed indicators of transparency with completeness of reporting, according to the CONSORT statement, and data sharing. We evaluated a selection of reporting items for a sample of randomized controlled trials (RCTs) studying CRC with published full-text articles between 2021–03-22 and 2018–03-22. Selected items were issued from the previously published CONSORT based peer-review tool (COBPeer tool). Then, we evaluated selective reporting through retrospective registration and primary outcome(s) switching between registration and publication. Finally, we determined if primary outcome(s) switching favored significant outcomes.

Results

We evaluated 101 RCTs with published full-text articles between 2021–03-22 and 2018–03-22. Five trials (5%) reported all selected CONSORT items completely. Seventy-four (73%), 53 (52%) and 13 (13%) trials reported the primary outcome(s), the allocation concealment process and harms completely. Twenty-five (25%) trials were willing to share data. In our sample, 49 (49%) trials were retrospectively registered and 23 (23%) trials had primary outcome(s) switching. The influence of primary outcome(s) switching could be evaluated in 16 (16/23 = 70%) trials, with 6 (6/16 = 38%) trials showing a discrepancy that favored statistically significant results.

Conclusions

Our results highlight a lack of transparency as well as frequent selective reporting in interventional trials studying CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09334-5.

A web-based tool for automatically linking clinical trials to their publications

OBJECTIVE

Evidence synthesis teams, physicians, policy makers, and patients and their families all have an interest in following the outcomes of clinical trials and would benefit from being able to evaluate both the results posted in trial registries and in the publications that arise from them. Manual searching for publications arising from a given trial is a laborious and uncertain process. We sought to create a statistical model to automatically identify PubMed articles likely to report clinical outcome results from each registered trial in ClinicalTrials.gov.

MATERIALS AND METHODS

A machine learning-based model was trained on pairs (publications known to be linked to specific registered trials). Multiple features were constructed based on the degree of matching between the PubMed article metadata and specific fields of the trial registry, as well as matching with the set of publications already known to be linked to that trial.

RESULTS

Evaluation of the model using known linked articles as gold standard showed that they tend to be top ranked (median best rank = 1.0), and 91% of them are ranked in the top 10.

DISCUSSION

Based on this model, we have created a free, public web-based tool that, given any registered trial in ClinicalTrials.gov, presents a ranked list of the PubMed articles in order of estimated probability that they report clinical outcome data from that trial. The tool should greatly facilitate studies of trial outcome results and their relation to the original trial designs.

Clinical trial registries as Scientometric data: A novel solution for linking and deduplicating clinical trials from multiple registries

Registries of clinical trials are a potential source for scientometric analysis of medical research and serve important functions for the research community and the public at large. Clinical trials that recruit patients in Germany are usually registered in the German Clinical Trials Register (DRKS) or in international registries such as ClinicalTrials.gov. Furthermore, the International Clinical Trials Registry Platform (ICTRP) aggregates trials from multiple primary registries. We queried the DRKS, ClinicalTrials.gov, and the ICTRP for trials with a recruiting location in Germany. Trials that were registered in multiple registries were linked using the primary and secondary identifiers and a Random Forest model based on various similarity metrics. We identified 35,912 trials that were conducted in Germany. The majority of the trials was registered in multiple databases. 32,106 trials were linked using primary IDs, 26 were linked using a Random Forest model, and 10,537 internal duplicates on ICTRP were identified using the Random Forest model after finding pairs with matching primary or secondary IDs. In cross-validation, the Random Forest increased the F1-score from 96.4% to 97.1% compared to a linkage based solely on secondary IDs on a manually labelled data set. 28% of all trials were registered in the German DRKS. 54% of the trials on ClinicalTrials.gov, 43% of the trials on the DRKS and 56% of the trials on the ICTRP were pre-registered. The ratio of pre-registered studies and the ratio of studies that are registered in the DRKS increased over time.

Factors associated with successful phase III trials for solid tumors: A systematic review

Background

It is known that the success rates of phase III trials for solid cancers are low. The aim of this study was to investigate factors related to trial design and operation that were associated with the probability of the success of phase III trials for solid cancers based on the latest comprehensive data.

Methods

Relevant clinical trials, started between September 2007 and December 2017, were retrieved from ClinicalTrials.gov. Then, variables related to the selected trials such as types of primary endpoint and duration of trial enrollment were collected from the literature and ClinicalTrials.gov. Based on the collected data, a multivariate logistic regression analysis was conducted to find factors associated with the successful results.

Results

Four hundred phase III trials were found eligible for the study. Unsuccessful trials were 207 and successful trials were 193. As a result of multivariate logistic regression analysis, factors that presented a statistically significant relationship were primary endpoint (Odds ratio [OR]: 2.79 [95% CI: 1.59–4.89]), control arm (OR: 3.06 [95% CI: 1.39–6.73]), start year of trial (OR: 3.28 [95% CI: 1.87–5.77]), and duration of trial enrollment (OR: 0.77 [95% CI: 0.60–0.99]).

Conclusion

Type of primary endpoints (time-to-event endpoints other than overall survival), control arm (treatments with lower evidence level, placebo or best supportive care), and duration of trial enrollment (faster enrollment speed) were associated with phase III trial success.

Reliability of Trial Information Across Registries for Trials With Multiple Registrations: A Systematic Review

IMPORTANCE

Clinical trial registries are important for gaining an overview of ongoing research efforts and for deterring and identifying publication bias and selective outcome reporting. The reliability of the information in trial registries is uncertain.

OBJECTIVE

To assess the reliability of information across registries for trials with multiple registrations.

EVIDENCE REVIEW

For this systematic review, 360 protocols of randomized clinical trials (RCTs) approved by research ethics committees in Switzerland, the UK, Canada, and Germany in 2012 were evaluated. Clinical trial registries were searched from March to September 2019 for corresponding registrations of these RCTs. For RCTS that were recorded in more than 1 clinical trial registry, key trial characteristics that should be identical among all trial registries (ie, sponsor, funding source, primary outcome, target sample size, trial status, date of first patient enrollment, results available, and main publication indexed) were extracted in duplicate. Agreement between the different trial registries for these key characteristics was analyzed descriptively. Data analyses were conducted from May 1 to November 30, 2020. Representatives from clinical trial registries were interviewed to discuss the study findings between February 1 and March 31, 2021.

FINDINGS

The analysis included 197 RCTs registered in more than 1 trial registry (151 in 2 registries and 46 in 3 registries), with 188 trials in ClinicalTrials.gov, 185 in the European Union Drug Regulating Authorities Clinical Trials Database (EudraCT), 20 in ISRCTN, and 47 in other registries. The agreement of key information across all registries was as follows: 178 of 197 RCTs (90%; 95% CI, 85%-94%) for sponsor, 18 of 20 (90%; 95% CI, 68%-99%) for funding source (funding was not reported on ClinicalTrials.gov), 154 of 197 (78%; 95% CI, 72%-84%) for primary outcome, 90 of 197 (46%; 95% CI, 39%-53%) for trial status, 122 of 194 (63%; 95% CI, 56%-70%) for target sample size, and 43 of 57 (75%; 95% CI, 62%-86%) for the date of first patient enrollment when the comparison time was increased to 30 days (date of first patient enrollment was not reported on EudraCT). For results availability in trial registries, agreement was 122 of 197 RCTs (62%; 95% CI, 55%-69%) for summary data reported in the registry and 91 of 197 (46%; 95% CI, 39%-53%) for whether a published article with the main results was indexed. Different legal requirements were stated as the main reason for inconsistencies by representatives of clinical trial registries.

CONCLUSIONS AND RELEVANCE

In this systematic review, for a substantial proportion of registered RCTs, information about key trial characteristics was inconsistent across trial registries, raising concerns about the reliability of the information provided in these registries. Further harmonization across clinical trial registries may be necessary to increase their usefulness.

Clinical trials and tribulations: lessons from spinal cord injury studies registered on ClinicalTrials.gov

STUDY DESIGN

Article.

OBJECTIVE

ClinicalTrials.gov is an online trial registry that provides public access to information on past, present, and future clinical trials. While increasing transparency in research, the quality of the information provided in trial registrations is highly variable. The objective of this study is to assess key areas of information on ClinicalTrials.gov in interventional trials involving people with spinal cord injuries.

SETTING

Interventional trials on ClinicalTrials.gov involving people with spinal cord injuries.

METHODS

A subset of data on interventional spinal cord injury trials was downloaded from ClinicalTrials.gov. Reviewers extracted information pertaining to study type, injury etiology, spinal cord injury characteristics, timing, study status, and results.

RESULTS

Of the interventional trial registrations reviewed, 62.5%, 58.6%, and 24.3% reported injury level, severity, and etiology, respectively. The timing of intervention relative to injury was reported in 72.8% of registrations. Most trials identified a valid study status (89.2%), but only 23.5% of those completed studies had posted results.

CONCLUSIONS

Our review provides a snapshot of interventional clinical trials conducted in the field of spinal cord injury and registered in ClinicalTrials.gov. Areas for improvement were identified with regards to reporting injury characteristics, as well as posting results.

Differences in pediatric versus adult clinical trial characteristics for atopic dermatitis

BACKGROUND

Atopic dermatitis (AD) is a growing burden in all ages. The aim of this study was to compare trial characteristics between pediatric and adult AD trials.

METHODS

Data were collected from ClinicalTrials.gov on AD therapeutic trials completed between 2003 and 2019. The trials were classified as pediatrics (mean or median age <18 years of the experimental group participants) or adults. The trials with and without results on ClinicalTrials.gov were searched on PubMed for further data collection.

RESULTS

Of 210 trials, 50 (24%) were pediatric trials [mean age: 8.2 ± 4.3 years (SD)] and 160 (76%) were adult trials [mean age 35.2 ± 5.7 years (SD)]. Pediatric and adult trials were equally likely to be randomized controlled trials; however, pediatric trials were more likely to be open-label trials (P < .001) and have no comparator (P < .001). Adult trials were more likely to be industry-funded (95% vs. 80%, P = .001). Any evaluation of drug safety was more likely present in adult trials (83% vs. 60%, P = .001). In trials examining AD severity as an outcome, the Eczema Area and Severity Index (EASI) predominated in adult trials (51% vs. 29%, P < .05) and Scoring Atopic Dermatitis (SCORAD) in pediatric trials (25% vs. 10%, P < .05).

CONCLUSION

The results highlight differences in trial design between pediatric and adult AD trials and show a lack of standardization in trial design.

The Use of Patient-Reported Outcome Measures in Phase I Oncology Clinical Trials

OBJECTIVE

To investigate patient-reported outcome (PRO) usage in phase I oncology clinical trials, including types of PRO measures and changes over time.

METHODS

We analyzed ClinicalTrials.gov records of phase I oncology clinical trials completed by December 2019.

RESULTS

Of all eligible trials, 2.3% (129/5,515) reported ≥1 PRO, totaling 181 instances of PRO usage. PRO usage increased over time, from 0.6% (trials initiated before 2000) to 3.4% (trials starting between 2015 and 2019). The most common PRO measures were unspecified (29%), tumor-specific (24%), and generic cancer (19%).

CONCLUSION

Although uncommon in phase I oncology clinical trials, PRO usage is increasing over time. PRO measures were often unspecified on ClinicalTrials.gov, suggesting that more precise reporting and standardization are needed.

Missing clinical trial data: the evidence gap in primary data for potential COVID-19 drugs

Background

Several drugs are being repurposed for the treatment of the coronavirus disease 2019 (COVID-19) pandemic based on in vitro or early clinical findings. As these drugs are being used in varied regimens and dosages, it is important to enable synthesis of existing safety data from clinical trials. However, availability of safety information is limited by a lack of timely reporting of overall clinical trial results on public registries or through academic publication. We aimed to analyse the evidence gap in this data by conducting a rapid review of results posting on ClinicalTrials.gov and in academic publications to quantify the number of trials missing results for drugs potentially being repurposed for COVID-19.

Methods

ClinicalTrials.gov was searched for 19 drugs that have been identified as potential treatments for COVID-19. Relevant clinical trials for any prior indication were listed by identifier (NCT number) and checked for results and for timely result reporting (within 395 days of the primary completion date). Additionally, PubMed and Google Scholar were searched to identify publications of results not listed on the registry. A second, blinded search of 10% of trials was conducted to assess reviewer concordance.

Results

Of 3754 completed trials, 1516 (40.4%) did not post results on ClinicalTrials.gov or in the academic literature. Tabular results were available on ClinicalTrials.gov for 1172 (31.2%) completed trials. A further 1066 (28.4%) had published results in the academic literature, but did not report results on ClinicalTrials.gov. Key drugs missing clinical trial results include hydroxychloroquine (37.0% completed trials unreported), favipiravir (77.8%) and lopinavir (40.5%).

Conclusions

There is an important evidence gap for the safety of drugs being repurposed for COVID-19. This uncertainty could cause unnecessary additional morbidity and mortality during the pandemic. We recommend caution in experimental drug use for non-severe disease and urge clinical trial sponsors to report missing results retrospectively.

Clinical applicability of natural products for prevention and treatment of oral mucositis: a systematic review and meta-analysis

OBJECTIVE

A systematic review and meta-analysis was carried out to verify evidence regarding the efficacy and safety of the clinical applicability of natural products in the prevention and treatment of oral mucositis induced by chemotherapy and/or radiotherapy.

METHODOLOGY

An electronic research according to the PICOS strategy, using the terms "natural products" and "oral mucositis," was carried out at Pubmed, Cochrane, Embase, and "gray literature." The stages of eligibility, data extraction, and quality assessment of the studies were carried out independently and in duplicate.

RESULTS

The number of studies identified as eligible was 151, including 47 randomized controlled trials, reporting a total of 3075 participants undergoing some therapy with natural products on oral mucositis. The included clinical trials covered a variety of 31 types of natural products. Considering the risk of bias of the clinical trials, 24 studies (51.1%) were considered to have a low overall risk of bias, nine (19.1%) were at moderate risk, and 14 clinical trials (29.8%) were at high risk of bias. Honey was the most assessed natural agent. Fourteen studies (3.4%) reported that natural agents reduced pain.

CONCLUSION

The results of the meta-analysis support a positive effect of honey and Aloe vera in reducing mucositis in patients receiving cancer therapy.

CLINICAL RELEVANCE

The results found add relevant information to the scientific community regarding the prevention and treatment of mucositis. Graphical abstract.

Chinese medicine formulas for nonalcoholic fatty liver disease: Overview of systematic reviews

BACKGROUND

Nonalcoholic fatty liver disease (NAFLD) affects more than one-quarter of the global population. Due to the lack of approved chemical agents, many patients seek treatment from traditional Chinese medicine (TCM) formulas. A variety of systematic reviews have been published regarding the effectiveness and safety of TCM formulas for NAFLD.

AIM

To critically appraise available systematic reviews and sort out the high-quality evidence on TCM formulas for the management of NAFLD.

METHODS

Seven databases were systematically searched from their inception to 28 February 2020. The search terms included “non-alcoholic fatty liver disease,” “Chinese medicines,” “systematic review,” and their synonyms. Systematic reviews involving TCM formulas alone or in combination with conventional medications were included. The methodological quality and risk of bias of eligible systematic reviews were evaluated by using A Measure Tool to Assess Systematic Reviews 2 (AMSTAR 2) and Risk of Bias in Systematic Review (ROBIS). The quality of outcomes was assessed by the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

RESULTS

Seven systematic reviews were ultimately included. All systematic reviews were conducted based on randomized controlled trials and published in the last decade. According to the AMSTAR 2 tool, one systematic review was judged as having a moderate confidence level, whereas the other studies were rated as having a low or extremely low level of confidence. The ROBIS tool showed that the included systematic reviews all had a high risk of bias due to insufficient consideration of identified concerns. According to the GRADE system, only two outcomes were determined as high quality; namely, TCM formulas with the HuoXueHuaYu principle were better than conventional medications in ultrasound improvement, and TCM formulas were superior to antioxidants in alanine aminotransferase normalization. Other outcomes were downgraded to lower levels, mainly because of heterogeneity among studies, not meeting optimal information sample size, and inclusion of excessive numbers of small sample studies. Nevertheless, the evidence quality of extracted outcomes should be further downgraded when applying to clinical practice due to indirectness.

CONCLUSION

The quality of available systematic reviews was not satisfactory. Researchers should avoid repeatedly conducting systematic reviews in this area and focus on designing rigorous randomized controlled trials to support TCM formula applications.

Obstacles to the reuse of study metadata in ClinicalTrials.gov

Metadata that are structured using principled schemas and that use terms from ontologies are essential to making biomedical data findable and reusable for downstream analyses. The largest source of metadata that describes the experimental protocol, funding, and scientific leadership of clinical studies is ClinicalTrials.gov. We evaluated whether values in 302,091 trial records adhere to expected data types and use terms from biomedical ontologies, whether records contain fields required by government regulations, and whether structured elements could replace free-text elements. Contact information, outcome measures, and study design are frequently missing or underspecified. Important fields for search, such as condition and intervention, are not restricted to ontologies, and almost half of the conditions are not denoted by MeSH terms, as recommended. Eligibility criteria are stored as semi-structured free text. Enforcing the presence of all required elements, requiring values for certain fields to be drawn from ontologies, and creating a structured eligibility criteria element would improve the reusability of data from ClinicalTrials.gov in systematic reviews, metanalyses, and matching of eligible patients to trials.

Using the concept of "deserved trust" to strengthen the value and integrity of biomedical research

It is commonplace for science leaders and others to claim that the future of biomedical research rests in large part upon the public's trust. If true, it behooves the biomedical research community to understand how it avoids taking chances with that trust. This commentary, which builds upon comments of noted trust scholar Russell Hardin about how best to enjoy trust, assumes that the key to being trusted is deserving to be trusted. Thus, it proposes using "deserved trust" to identify ways that the public's trust in biomedical research could be better supported. Employing deserved trust to support the public's trust leads us to consider what it is that the biomedical research community should be trusted to do, examine the evidence about the effectiveness of current safeguards meant to assure that those things routinely get done, and identify new ways to equip individual researchers, research teams, and research institutions to assure that the public's trust in their research is deserved rather than misplaced.

The quality of reporting general safety parameters and immune-related adverse events in clinical trials of FDA-approved immune checkpoint inhibitors

BACKGROUND

While immune-checkpoint inhibitors (ICIs) have transformed the field of oncology for advanced-stage cancers, they can lead to serious immune toxicities. Several systematic reviews have evaluated the risk of immune-related adverse events (irAEs); however, most have focused on published articles without evaluating trial registries. The objective of this methodological review was to compare the quality of reporting of safety information and in particular, serious irAEs (irSAEs), in both publications and ClinicalTrials.gov for all current FDA-approved ICIs.

METHODS

PubMed was searched to retrieve all published phase III randomized controlled trials (RCTs) evaluating ICIs. For each eligible trial, we searched for corresponding registration on ClinicalTrials.gov and extracted relevant safety data from both the publication and results posted on registry. We then compared the quality of reporting and the value of safety data between both sources.

RESULTS

Of 42 eligible published trials, 34 had results posted on ClinicalTrials.gov . Considerable variability was noted in the reporting of safety in both sources. SAEs were reported for all trial results in ClinicalTrials.gov compared to 23.5% of publications. An overall incidence for irAEs and irSAEs was reported in 58.8 and 8.8% of publications respectively, compared to 11.8 and 5.9% in registry results. Comparing the value of specific irSAEs was not possible between the two sources in 32/34 trials either due to different reporting formats (61.8%) or data not being reported in one or both sources (32.4%). From the 2 studies with compatible irSAE format, only 1 had matching data in both sources.

CONCLUSIONS

The reporting of irAEs / irSAEs varies considerably in publications and registries, which outlines the importance of standardizing the terminologies and methodologies for reporting safety information relevant to ICIs.

A meta-analysis on immune checkpoint inhibitor efficacy for advanced non-small cell lung cancer between East Asians versus non-East Asians

Background

We conducted a meta-analysis to assess the efficacy of immune checkpoint inhibitors (ICIs) (PD-1/L1 and CTLA-4 inhibitors) in first and subsequent lines in East Asians and non-East Asians.

Methods

We searched PubMed-MEDLINE, Embase and Scopus, from inception to 20 Sep 2019, and reviewed major conferences’ abstracts, for randomised controlled trials of ICI in advanced-stage NSCLC (Stage IIIB or IV) without EGFR mutation that reported hazard ratios (HRs) stratified by geographical region including the region “Asia” or “East Asia”. The primary outcome measures were overall survival (OS) and progression-free survival (PFS). The pooled HR and its 95% confidence interval (CI) for OS and PFS in East Asians and non-East Asians were calculated using a random effect model and the difference compared using an interaction test.

Results

A total of 5,465 patients from 7 randomised controlled trials involving CTLA-4 and/or PD-1/L1 inhibitors were included, with 1,740 (32%) East Asians and 3,725 (68%) non-East Asians. ICI was associated with an improvement in OS and PFS for both East Asian (OS HR, 0.74; 95% CI, 0.65–0.85; PFS HR, 0.56; 95% CI, 0.40–0.79) and non-East Asian patients (OS HR, 0.78; 95% CI, 0.72–0.85; PFS HR, 0.69; 95% CI, 0.56–0.85), with no significant difference between the two groups (P_interaction=0.55 for OS; P_interaction=0.33 for PFS). Subgroup analyses showed a statistically significant superior PFS (but not OS) for East Asians than non-East Asians in trials that used immune checkpoint inhibitor in the first-line treatment (P_interaction=0.02). No significant regional difference was found in further subgroups of pure ICI and combination of ICI with chemotherapy.

Conclusions

There is no significant difference in response to ICI between East Asians and non-East Asians with advanced stage NSCLC, and the statistically significant subgroup difference in PFS in the first line use of ICI may not be clinically significant.

Rescuing Informed Consent: How the new "Key Information" and "Reasonable Person" Provisions in the Revised U.S. Common Rule open the door to long Overdue Informed Consent Disclosure Improvements and why we need to walk Through that door

There is substantial published evidence showing that countless people enroll each year in ethically deficient clinical trials. Many of the trials are problematic because the quality of the science used to justify their launch may not be sufficiently vetted while many other trials may lack requisite social value. This poses the question: why do people volunteer for them? The answer resides in large part in the fact that informed consent practices have historically masked, rather than disclosed, the information that would alert research candidates to the ethically problematic nature of the trials. The "reasonable person" and "key information" provisions in the revised US Common Rule create the opportunity to correct this historical shortcoming. Two sources are employed to shed light on what the "key information" is that should be disclosed to a "reasonable person": the original disclosure aims of the Nuremberg Code, as well as an extensive body of meta-research evidence. Those sources jointly support a range of new disclosures in the informed consent process that would unmask the heretofore undisclosed information. The resulting proposed new disclosures pertain to the overall success prospects of clinical trials, the quality of the prior research that both forms the basis of clinical trials and informs assessment of their risks and benefits, the potential social value of clinical trials, and the commercial purposes of clinical trials.