Project description:ObjectiveTo measure the rate of non-publication and assess possible publication bias in clinical trials of electronic health records.MethodsWe searched ClinicalTrials.gov to identify registered clinical trials of electronic health records and searched the biomedical literature and contacted trial investigators to determine whether the results of the trials were published. Publications were judged as positive, negative, or neutral according to the primary outcome.ResultsSeventy-six percent of trials had publications describing trial results; of these, 74% were positive, 21% were neutral, and 4% were negative (harmful). Of unpublished studies for which the investigator responded, 43% were positive, 57% were neutral, and none were negative; the lower rate of positive results was significant (p<0.001).ConclusionThe rate of non-publication in electronic health record studies is similar to that in other biomedical studies. There appears to be a bias toward publication of positive trials in this domain.
Project description:ObjectiveTo estimate the frequency with which results of large randomized clinical trials registered with ClinicalTrials.gov are not available to the public.DesignCross sectional analysisSettingTrials with at least 500 participants that were prospectively registered with ClinicalTrials.gov and completed prior to January 2009.Data sourcesPubMed, Google Scholar, and Embase were searched to identify published manuscripts containing trial results. The final literature search occurred in November 2012. Registry entries for unpublished trials were reviewed to determine whether results for these studies were available in the ClinicalTrials.gov results database.Main outcome measuresThe frequency of non-publication of trial results and, among unpublished studies, the frequency with which results are unavailable in the ClinicalTrials.gov database.ResultsOf 585 registered trials, 171 (29%) remained unpublished. These 171 unpublished trials had an estimated total enrollment of 299,763 study participants. The median time between study completion and the final literature search was 60 months for unpublished trials. Non-publication was more common among trials that received industry funding (150/468, 32%) than those that did not (21/117, 18%), P=0.003. Of the 171 unpublished trials, 133 (78%) had no results available in ClinicalTrials.gov.ConclusionsAmong this group of large clinical trials, non-publication of results was common and the availability of results in the ClinicalTrials.gov database was limited. A substantial number of study participants were exposed to the risks of trial participation without the societal benefits that accompany the dissemination of trial results.
Project description:ImportanceDuplicate publications of randomized clinical trials are prevalent in the health-related literature. To date, few studies have assessed the interaction between duplicate publication and the language of the original publication.ObjectiveTo assess the existence of duplicate publication and the extent to which duplicate publication is associated with the language of the original publication.Design, setting, and participantsIn this retrospective cohort study, eligible randomized clinical trials were retrieved from trial registries, and bibliographic databases were searched to determine their publication status. Eligible randomized clinical trials were for drug interventions from January 1, 2008, to December 31, 2014. The search and analysis were conducted from March 1 to August 31, 2019. The trial registries were either primary registries recognized by the World Health Organization or the Drug Clinical Trial Registry Platform sponsored by the China Food and Drug Administration.ExposuresIndividual randomized clinical trials with positive vs negative results.Main outcomes and measuresJournal articles were classified as main articles (determined by largest sample size and longest follow-up among all journal articles derived from that randomized clinical trial) and duplicates. The duplicates were classified into 4 types: (1) unreferenced subgroup analysis (article did not disclose itself as a subgroup analysis or reference its main article); (2) unreferenced republication (article did not disclose itself as a replicate of the main article or reference it); (3) unreferenced interim analysis (article did not disclose itself as an interim analysis or reference its main article); and (4) partial duplicate (article did not disclose its sharing a subset of participants with other articles or reference them).ResultsAmong 470 randomized clinical trials published by August 2019 as journal articles, 55 (11.7%) had 75 duplicates, of which 53 (70.7%) were cross-language duplicates. Of the 75 duplicates, 33 (44.0%) were unreferenced republications, 25 (33.3%) unreferenced subgroup analyses, 15 (20.0%) unreferenced interim analyses, and 2 (2.7%) partial duplicates. When the main article of a randomized clinical trial was published in Chinese, those with positive findings were 2.48 (95% CI, 1.08-5.71) times more likely to have subsequent duplicate publication than those with negative findings.Conclusions and relevanceIn this study, most duplicates were cross-language duplicates and the most common type was unreferenced republication of the main article. Duplicate publication bias exists when the main articles of randomized clinical trials were published in Chinese, potentially misleading readers and compromising journals and evidence synthesis.
Project description:BackgroundClinical research should provide reliable evidence to clinicians, health policy makers, and researchers. The reliability of evidence will be assured once study planning, conducting, and reporting of results are transparent. The present research investigates publication rates, time until publication, and characteristics of clinical trials on medicinal products associated with timely publication of results, measures of scientific impact, authorship, and open access publication.MethodsClinical trials authorized in Hungary in 2012 were followed until publication and/or June 2020. Corresponding scientific publications were searched via clinical trial registries, PubMed (MEDLINE), and Google.ResultsOverall, 330 clinical trials were authorized in 2012 of which 232 trials were completed for more than 1 year in June 2020. The proportion of industry initiation was high (97%). Time to publication was 21 (22) months [median (IQR)]. Time to publication was significantly shorter when trials involved both European and non-European countries (26 vs 69 months [median]; hazard ratio = 0.38, 95% CI 0.22-0.66, p< 0.001), and were registered in both EU CTR and clinicaltrials.gov (27 vs 88 months; hazard ratio = 0.24, 95% CI 0.11-0.54; p< 0.001) based on survival analyses. A significant amount (24.1%) of unpublished clinical trial results were accessible in a trial register. The majority of available publications were published "open access" (70.93%). A minority of identified publications had a Hungarian author (21.5%).ConclusionsWe encourage academic researchers to plan, register and conduct trials on medicinal products. Registries should be considered as an important source of information of clinical trial results. Publications with domestic co-authors contribute to the research output of a country. Measurable domestic scientific impact of trials on medicinal products needs further improvement.
Project description:The United States (US) Food and Drug Administration (FDA) approves new drugs based on sponsor-submitted clinical trials. The publication status of these trials in the medical literature and factors associated with publication have not been evaluated. We sought to determine the proportion of trials submitted to the FDA in support of newly approved drugs that are published in biomedical journals that a typical clinician, consumer, or policy maker living in the US would reasonably search.We conducted a cohort study of trials supporting new drugs approved between 1998 and 2000, as described in FDA medical and statistical review documents and the FDA approved drug label. We determined publication status and time from approval to full publication in the medical literature at 2 and 5 y by searching PubMed and other databases through 01 August 2006. We then evaluated trial characteristics associated with publication. We identified 909 trials supporting 90 approved drugs in the FDA reviews, of which 43% (394/909) were published. Among the subset of trials described in the FDA-approved drug label and classified as "pivotal trials" for our analysis, 76% (257/340) were published. In multivariable logistic regression for all trials 5 y postapproval, likelihood of publication correlated with statistically significant results (odds ratio [OR] 3.03, 95% confidence interval [CI] 1.78-5.17); larger sample sizes (OR 1.33 per 2-fold increase in sample size, 95% CI 1.17-1.52); and pivotal status (OR 5.31, 95% CI 3.30-8.55). In multivariable logistic regression for only the pivotal trials 5 y postapproval, likelihood of publication correlated with statistically significant results (OR 2.96, 95% CI 1.24-7.06) and larger sample sizes (OR 1.47 per 2-fold increase in sample size, 95% CI 1.15-1.88). Statistically significant results and larger sample sizes were also predictive of publication at 2 y postapproval and in multivariable Cox proportional models for all trials and the subset of pivotal trials.Over half of all supporting trials for FDA-approved drugs remained unpublished >/= 5 y after approval. Pivotal trials and trials with statistically significant results and larger sample sizes are more likely to be published. Selective reporting of trial results exists for commonly marketed drugs. Our data provide a baseline for evaluating publication bias as the new FDA Amendments Act comes into force mandating basic results reporting of clinical trials.
Project description:PurposeWe describe the clinical pharmacology characterization of giredestrant in a first-in-human study.Experimental designThis phase Ia/Ib dose-escalation/-expansion study (NCT03332797) evaluated the safety, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of giredestrant in estrogen receptor-positive HER2-negative locally advanced/metastatic breast cancer. The single-agent dose-escalation stage evaluated giredestrant 10, 30, 90, or 250 mg once daily. The dose-expansion stage evaluated single-agent giredestrant at 30, 100, and 250 mg once daily. Dose-escalation and -expansion phases also evaluated giredestrant 100 mg combined with palbociclib 125 mg.ResultsFollowing single-dose oral administration, giredestrant was rapidly absorbed and generally showed a dose-proportional increase in exposure at doses ranging from 10 to 250 mg. At the 30 mg clinical dose, maximum plasma concentration was 266 ng/mL (50.1%) and area under the concentration-time curve from 0 to 24 hours at steady state was 4,320 ng·hour/mL (59.4%). Minimal giredestrant concentrations were detected in urine, indicating that renal excretion is unlikely to be a major elimination route for giredestrant. Mean concentration of 4beta-hydroxycholesterol showed no apparent increase over time at both the clinical dose (30 mg) and a supratherapeutic dose (90 mg), suggesting that giredestrant may have low CYP3A induction potential in humans. No clinically relevant drug-drug interaction was observed between giredestrant and palbociclib. Giredestrant exposure was not affected by food and was generally consistent between White and Asian patients.ConclusionsThis study illustrates how the integration of clinical pharmacology considerations into early-phase clinical trials can inform the design of pivotal studies and accelerate oncology drug development.SignificanceThis work illustrates how comprehensive clinical pharmacology characterization can be integrated into first-in-human studies in oncology. It also demonstrates the value of understanding clinical pharmacology attributes to inform eligibility, concomitant medications, and combination dosing and to directly influence late-stage trial design and accelerate development.
Project description:ImportanceAs medical knowledge and clinical practice rapidly evolve over time, there is an imperative to publish results of clinical trials in a timely way and reduce unnecessary delays.ObjectivesTo characterize the age of clinical trial data at the time of publication in journals with a high impact factor and highlight the time from final data collection to publication.Design and settingA cross-sectional analysis was conducted of all randomized clinical trials published from January 1 through December 31, 2015, in the Annals of Internal Medicine, BMJ, JAMA, JAMA Internal Medicine, Lancet, and New England Journal of Medicine. Multivariable linear regression analyses were conducted to assess whether data age (adjusted for follow-up duration) and publication time were associated with trial characteristics.Main outcomes and measuresThe outcome measures were the midpoint of data collection until publication (data age), the time from first participant enrollment to last participant enrollment (enrollment time), and the time from final data collection to publication (publication time).ResultsThere were 341 clinical trials published in 2015 by the 6 journals. For assessment of the primary end point, 37 trials (10.9%) had a follow-up period of less than 1 month, 172 trials (50.4%) had a follow-up period of 1 month to 1 year, and 132 trials (38.7%) had a follow-up period of more than 1 year. For all trials, the median data age at publication was 33.9 months (interquartile range, 23.5-46.3 months). Among trials with a follow-up period of 1 month or less, the median data age was 30.6 months (interquartile range, 18.6-39.0 months). A total of 68 trials (19.9%) required more than 4 years to complete enrollment. The median time from the completion of data collection to publication was 14.8 months (interquartile range, 7.4-22.2 months); publication time was 2 or more years in 63 trials (18.5%). In multivariable regression analyses adjusted for follow-up time, inconclusive or unfavorable trial results were significantly associated with older data age (>235 days). Compared with trials funded only by private industry, trials funded by government were associated with a significantly longer time to publication (>180 days).Conclusions and relevanceClinical trials in journals with a high impact factor were published with a median data age of nearly 3 years. For a substantial proportion of studies, time for enrollment and time from completion of data collection to publication were quite long, indicating marked opportunities for improvement in clinical trials to reduce data age.
Project description:The paper describes T/Gen, a prototype computer-based tool designed to help maintain the knowledge in a computer-based clinical practice guideline that provides patient-specific recommendations. T/Gen takes as input a set of clinical conditions to which a guideline must react, and allows the user to specify domain-specific constraints as to which combinations of conditions do not make sense or do not need to be exhaustively tested against one another. T/Gen automatically generates constrained sets of combinations of clinical conditions, each corresponding to a clinical case (or to several closely related clinical cases) that can be used to help test the computer-based guideline. The combinations can be used to test the guideline logic using T/Gen's built-in logic interpreter, or to generate a set of test cases for use in testing an operational guideline system. T/Gen has been developed and tested with five pilot guidelines, for two childhood immunization series, for influenza vaccination, for primary thyroid screening, and for embryo transplantation. The paper describes how T/Gen's approach is implemented for the five pilot guidelines, outlines the current status and future directions of the project, and discusses the design issues that arose in the course of carrying out the work.
Project description:BackgroundScreening to identify individuals with elevated brain amyloid (Aβ+) for clinical trials in Preclinical Alzheimer's Disease (PAD), such as the Anti-Amyloid Treatment in Asymptomatic Alzheimer's disease (A4) trial, is slow and costly. The Trial-Ready Cohort in Preclinical/Prodromal Alzheimer's Disease (TRC-PAD) aims to accelerate and reduce costs of AD trial recruitment by maintaining a web-based registry of potential trial participants, and using predictive algorithms to assess their likelihood of suitability for PAD trials.ObjectivesHere we describe how algorithms used to predict amyloid burden within TRC-PAD project were derived using screening data from the A4 trial.DesignWe apply machine learning techniques to predict amyloid positivity. Demographic variables, APOE genotype, and measures of cognition and function are considered as predictors. Model data were derived from the A4 trial.SettingTRC-PAD data are collected from web-based and in-person assessments and are used to predict the risk of elevated amyloid and assess eligibility for AD trials.ParticipantsPre-randomization, cross-sectional data from the ongoing A4 trial are used to develop statistical models.MeasurementsModels use a range of cognitive tests and subjective memory assessments, along with demographic variables. Amyloid positivity in A4 was confirmed using positron emission tomography (PET).ResultsThe A4 trial screened N=4,486 participants, of which N=1323 (29%) were classified as Aβ+ (SUVR ≥ 1.15). The Area under the Receiver Operating Characteristic curves for these models ranged from 0.60 (95% CI 0.56 to 0.64) for a web-based battery without APOE to 0.74 (95% CI 0.70 to 0.78) for an in-person battery. The number needed to screen to identify an Aβ+ individual is reduced from 3.39 in A4 to 2.62 in the remote setting without APOE, and 1.61 in the remote setting with APOE.ConclusionsPredictive algorithms in a web-based registry can improve the efficiency of screening in future secondary prevention trials. APOE status contributes most to predictive accuracy with cross-sectional data. Blood-based assays of amyloid will likely improve the prediction of amyloid PET positivity.
Project description:During the last decade Sweden has invested in a national infrastructure for collection of structured clinical data in the form of healthcare registries (in Sweden known as Kvalitetsregister). These data can be combined with other public data using the national personal identifiers that are issued to Swedish citizens. The healthcare registries have an almost complete coverage of Swedish healthcare, and a large network of clinicians is involved in the quality assurance and continuous improvement of healthcare using these registries. Uppsala Clinical Research Center (UCR) has been a technology provider of large-scale national registries and has a strong background in clinical trial management. This effort combines the areas of healthcare registries and clinical trials into a novel way of performing clinical trials to be able to: 1) run clinical trials as an integrated part of normal clinic workflow; and 2) leverage the nationwide network of outcome reporting. This strategy was shown to be successful in the TASTE (Thrombus Aspiration in Myocardial Infarction) study. When TASTE had been published, the New England Journal of Medicine wrote a perspective on the study calling it 'The randomized registry trial-the next disruptive technology in clinical research?' Since then several studies have been conducted in this way with great success. UCR has been appointed, by Clinical Studies Sweden and the Swedish Research Council, to develop the Swedish national guidelines for registry-based randomized clinical trials in order to ensure the possibility for more organizations to run this kind of study. This paper describes key concepts of register-based randomized clinical trials and the development of Swedish national guidelines.