Discontinuation and non-publication of randomised clinical trials supported by the main public funding body in Switzerland: a retrospective cohort study

Analysis of the discontinuation and nonpublication of neurooncological randomized clinical trials

Background

Premature discontinuation and nonpublication of clinical trials contribute to research waste and compromise our ability to improve patient outcomes. However, the extent to which these problems exist in neurooncological randomized clinical trials (RCTs) is not known. This study aimed to evaluate the prevalence of discontinuation and nonpublication of neurooncological RCTs, identify contributing factors, and assess trial characteristics associated with each.

Methods

We performed a retrospective, cross-sectional study of neurooncological RCTs registered in Clinicaltrials.gov before March 7, 2023. Data were collected from Clinicaltrials.gov and associated publications were located. We attempted to contact authors for all trials without associated publications or an identified reason for discontinuation.

Results

Of 139 included RCTs, 57 (41%) were discontinued. The most common reason for discontinuation identified was slow enrollment or accrual (23%), though 30 trials (53%) were discontinued for unknown reasons. Trials funded by sources other than industry or the National Institutes of Health were more likely to be discontinued (odds ratio 4.2, 95% confidence interval 1.3-13.8). In total, 67 of the 139 (48%) RCTs were unpublished, including 50 of the 57 (88%) discontinued studies and 17 of the 82 (21%) completed studies.

Conclusions

In our study, discontinuation of neurooncological clinical trials was common and often occurred for unknown reasons. Trials were also frequently unpublished, particularly those that were discontinued. Addressing these findings may provide an opportunity to reduce research waste and improve outcomes for patients with neurological cancers.

Therapies and Challenges in the Post-Stroke Aphasia Rehabilitation Arena: Current and Future Prospects

Aphasia is a serious consequence of stroke that results in a breakdown in communication. The course of aphasia recovery differs between afflicted individuals, and responsiveness to treatment cannot be predicted. Aphasiologists continue to investigate numerous behavioral treatment protocols that have shifted their focus to complimentary rehabilitation strategies. The aim of this study is threefold. First, to summarize the different categories of aphasia interventions post-stroke, considering their respective protocols, and present available evidence on the effectiveness of those protocols. Second, to document the challenges regarding the prediction of aphasia treatment response post-stroke in individual patients. Third, to report the challenges faced by researchers in recruiting people with aphasia (PWA) for treatment studies, and provide recommendations on how to increase participant recruitment and retention. This study provides up-to-date information on (i) effective therapies and aphasia recovery processes, and (ii) research recruitment hurdles together with potential strategies for overcoming them.

Completion and publication of clinical trials in a cooperative group: a cohort study of trials of the Swiss Group for Clinical Cancer Research (SAKK)

BACKGROUND

Premature trial discontinuation and non-publication of trial results are still major issues negatively affecting reliable evidence generation.

OBJECTIVES

To investigate trial completion and publication rate of cancer trials conducted within the Swiss Group for Clinical Cancer Research (SAKK).

DESIGN

Cohort study of clinical trials.

SETTING

Cohort of interventional cancer trials conducted in Switzerland with accrual closure between 1986 and 2021 identified from the SAKK trial management system.

OUTCOMES

Premature trial discontinuation and publication in peer-reviewed journal.

RESULTS

We included 261 trials; median number of recruited patients was 150.5 (range 1-8028). Most trials (67.0%) were randomised. Overall, 76 of 261 (29.1%) trials were prematurely closed for accrual. The three main reasons for premature closure were insufficient accrual in 28 trials, followed by stopping for futility in 17 or efficacy in 8 trials. We included 240 trials for the publication status (21 excluded, because 8 still in follow-up, for 10 the primary completion date was less than a year ago and for 3 the manuscript was submitted, but to accepted yet). 216 of 240 (90.0%) were published as a full article, 14 were published in other formats, leading to an overall publication rate of 95.8%. The rate of premature discontinuation declined over time, with 34.2%, 27.8% and 23.5% in trials activated before 2000, between 2000 and 2009, and since 2010, respectively. We observed an increasing publication rate in peer-reviewed journals over time: 79.2% (closed before 2000), 95.7% (closed between 2000 and 2009) and 93.2% (closed after 2010).

CONCLUSION

Insufficient patient recruitment is still the major reason for premature trial discontinuation. SAKK has continuously improved its quality management of trial conduct over time leading to increased successful trial completion and publication. However, there is still room for improvement to increase the number of trials reaching their target sample size.

Public reporting of clinical trial findings as an ethical responsibility to participants: a qualitative study

OBJECTIVE

To understand how the experiences and views of trial participants, trial investigators and others connected to clinical trial research relate to whether researchers have a duty to participants to publicly report research findings.

DESIGN

Qualitative interview study.

SETTING

Semistructured interviews held in person or by telephone between March 2019 and April 2021 with participants in the Canadian provinces of Alberta, British Columbia and Ontario.

PARTICIPANTS

34 participants, including 10 clinical trial participants, 17 clinical trial investigators, 1 clinical research coordinator, 3 research administrators and 3 research ethics board members.

ANALYSIS

We conducted a thematic analysis, including qualitative coding of interview transcripts and identification of key themes.

MAIN OUTCOME MEASURES

Key themes identified through qualitative coding of interview data.

RESULTS

Most clinical trial participants felt that reporting clinical trial results is important. Accounts of trial participants suggest their contributions are part of a reciprocal relationship involving the expectation that research will advance medical knowledge. Similarly, comments from trial investigators suggest that reporting trial results is part of reciprocity with trial participants and is a necessary part of honouring informed consent. Accounts of trial investigators suggest that when drug trials are not reported, this may undermine informed consent in subsequent trials by withholding information on harms or efficacy relevant to informed decisions on whether to conduct or enroll in future trials of similar drugs.

CONCLUSION

The views of trial participants, trial investigators and others connected to clinical trial research in Canada suggest that researchers have an obligation to participants to publicly report clinical trial results and that reporting results is necessary for honouring informed consent.

Considerations on the Obstacles That Lead to Slow Recruitment in a Pain Management Clinical Trial: Experiences from the Belgian PELICAN (PrEgabalin Lidocaine Capsaicin Neuropathic Pain) Pragmatic Study

Background

A qualitative evaluation study of the prematurely terminated PrEgabalin Lidocaine Capsaicin Neuropathic Pain (PELICAN) study was performed. The PELICAN study aimed to examine pain management for localized neuropathic pain (LNP), as epidemiological figures have shown a high percentage of LNP patients in Belgium. The study compared systemic and topical medications according to pain relief, adverse effects, and several measures of quality of life.

Objective

Achieving better study patient recruitment through qualitative research. To investigate and determine the causes of the observed recruitment problems in the PELICAN study, pain centers involved in the study as well as nonrecruiting pain centers were included. Furthermore, it aimed to highlight the positive and negative lessons learned from the conducted study and the number of obstacles the team had to overcome.

Methods

A qualitative study, using a mixed methods approach, was performed. Multiple pain centers in Belgium completed an online survey, after which a structured interview was conducted to elaborate the responses in more detail. The broad topics of these meetings were feedback about the study, reviewing survey answers, and actions undertaken to enhance recruitment.

Results

Different factors contributed to the low recruitment rate in the PELICAN study, such as limited and late referral from the general practitioners to the Belgian pain centers, insufficient internal referrals from nonpain specialists, lack of specific expertise on LNP in some centers, scarcity of staff, limited reimbursement to administer complex analgesic schemes, overestimation of the patient population, and the reluctance of patients to participate in pain research. Additionally, shortcomings in the implemented study design and the need for more logistical investments were identified.

Conclusion

The findings of the qualitative study demonstrate the need for further, more varied LNP research in Belgium, not limited to pharmacological studies. It also sheds important light on the recruitment obstacles that may be faced during these studies. Future studies could support this research by offering better proposals for feasibility and recruitment, for instance, by designing and conducting a compelling pilot study or applying social media during the recruitment phase. Clinical Trials. This trial is registered with NCT03348735. EUDRACT number 2018-003617-17.

Trial registration and time to publication in a retrospective cohort of publicly funded randomised controlled trials in New Zealand 1999-2017

OBJECTIVES

To determine how quickly randomised controlled trials funded by the Health Research Council of New Zealand (HRC) were registered and published, and whether time to publication differed by trial result.

DESIGN

We created a retrospective cohort of trials offered funding from 1999 to 2017 by seeking lists of candidate studies using the Official Information Act 1982. These lists were supplemented by searching the HRC's online research repository and an open-access database on Figshare. One investigator searched for trial registrations and for dissemination using electronic databases, university websites and ResearchGate. One investigator extracted data from the obtained studies and a second investigator independently corroborated the data entry from a 10% random sample.

RESULTS

We identified 258 trials that were offered funding, 252 trials were conducted and 229 (90.9%) were registered, 179 prospectively by the date of the final search (24 March 2022). Overall, 236 trials were completed by the date of the last search and in 209 (88.6%) trials the results had been disseminated, 200 (84.7%) of which were by journal publication. We obtained the results for 214 trials, 91 (42.5%) of which were positive, 120 (56.1%) of which were null and 3 (1.4%) of which were negative. Median time to publication was 22.7 months for positive trials and 21.5 months for combined null or negative trials (log rank test p=0.83). Median time since trial completion in the trials that had not been published was 43.6 months (IQR 17.1-108.2 months).

CONCLUSIONS

Between 1999 and 2017, almost 9 out of every 10 HRC-funded trials had been registered and a similar proportion of completed trials had been published with no difference in time to publication based on type of result. However, only a slim majority of trials had published within the 2-year time frame set by the WHO.

Which decentralised trial activities are reported in clinical trial protocols of drug trials initiated in 2019-2020? A cross-sectional study in ClinicalTrials.gov

OBJECTIVES

Decentralised clinical trial activities-such as participant recruitment via social media, data collection through wearables and direct-to-participant investigational medicinal product (IMP) supply-have the potential to change the way clinical trials (CTs) are conducted and with that to reduce the participation burden and improve generalisability. In this study, we investigated the decentralised and on-site conduct of trial activities as reported in CT protocols with a trial start date in 2019 or 2020.

DESIGN

We ascertained the decentralised and on-site conduct for the following operational trial activities: participant outreach, prescreening, screening, obtaining informed consent, asynchronous communication, participant training, IMP supply, IMP adherence monitoring, CT monitoring, staff training and data collection. Results were compared for the public versus private sponsors, regions involved, trial phases and four time periods (the first and second half of 2019 and 2020, respectively).

SETTING

Phases 2, 3 and 4 clinical drug trial protocols with a trial start date in 2019 or 2020 available from ClinicalTrials.gov.

OUTCOME MEASURES

The occurrence of decentralised and on-site conduct of the predefined trial activities reported in CT protocols.

RESULTS

For all trial activities, on-site conduct was more frequently reported than decentralised conduct. Decentralised conduct of the individual trial activities was reported in less than 25.6% of the 254 included protocols, except for decentralised data collection, which was reported in 68.9% of the protocols. More specifically, 81.9% of the phase 3 protocols reported decentralised data collection, compared with 73.3% and 47.0% of the phase 2 and 4 protocols, respectively. For several activities, including prescreening, screening and consenting, upward trends in reporting decentralised conduct were visible over time.

CONCLUSIONS

Decentralised methods are used in CTs, mainly for data collection, but less frequently for other activities. Sharing best practices and a detailed description in protocols can drive the adoption of decentralised methods.

Generalizability and reach of a randomized controlled trial to improve oral health among home care recipients: comparing participants and nonparticipants at baseline and during follow-up

Background

The generalizability of randomized controlled trials (RCTs) with a low response can be limited by systematic differences between participants and nonparticipants. This participation bias, however, is rarely investigated because data on nonparticipants is usually not available. The purpose of this article is to compare all participants and nonparticipants of a RCT to improve oral health among home care recipients at baseline and during follow-up using claims data.

Methods

Seven German statutory health and long-term care insurance funds invited 9656 home care recipients to participate in the RCT MundPflege. Claims data for all participants (n = 527, 5.5% response) and nonparticipants (n = 9129) were analyzed. Associations between trial participation and sex, age, care dependency, number of Elixhauser diseases, and dementia, as well as nursing, medical, and dental care utilization at baseline, were investigated using multivariable logistic regression. Associations between trial participation and the probability of (a) moving into a nursing home, (b) being hospitalized, and (c) death during 1 year of follow-up were examined via Cox proportional hazards regressions, controlling for baseline variables.

Results

At baseline, trial participation was positively associated with male sex (odds ratio 1.29 [95% confidence interval 1.08–1.54]), high (vs. low 1.46 [1.15–1.86]) care dependency, receiving occasional in-kind benefits to relieve caring relatives (1.45 [1.15–1.84]), having a referral by a general practitioner to a medical specialist (1.62 [1.21–2.18]), and dental care utilization (2.02 [1.67–2.45]). It was negatively associated with being 75–84 (vs. < 60 0.67 [0.50–0.90]) and 85 + (0.50 [0.37–0.69]) years old. For morbidity, hospitalizations, and formal, respite, short-term, and day or night care, no associations were found. During follow-up, participants were less likely to move into a nursing home than nonparticipants (hazard ratio 0.50 [0.32–0.79]). For hospitalizations and mortality, no associations were found.

Conclusions

For half of the comparisons, differences between participants and nonparticipants were observed. The RCT’s generalizability is limited, but to a smaller extent than one would expect because of the low response. Routine data provide a valuable source for investigating potential differences between trial participants and nonparticipants, which might be used by future RCTs to evaluate the generalizability of their findings.

Trial registration

German Clinical Trials Register DRKS00013517. Retrospectively registered on June 11, 2018.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06470-y.

Opportunities and Challenges for Decentralized Clinical Trials: European Regulators' Perspective

Decentralized clinical trials (DCTs) have the potential to improve accessibility, diversity, and retention in clinical trials by moving trial activities to participants’ homes and local surroundings. In this study, we conducted semi‐structured interviews with 20 European regulators to identify regulatory challenges and opportunities for the implementation of DCTs in the European Union. The key opportunities for DCTs that were recognized by regulators include a reduced participation burden, which could facilitate the participation of underserved patients. In addition, regulators indicated that data collected in DCTs are expected to be more representative of the real world. Key challenges recognized by regulators for DCTs include concerns regarding investigator oversight and participants’ safety when physical examinations and face‐to‐face contact are limited. To facilitate future learning, hybrid clinical trials with both on‐site and decentralized elements are proposed by the respondents.

New Horizons in Mild Hypoxic-ischemic Encephalopathy: A Standardized Algorithm to Move past Conundrum of Care

Hypoxic-ischemic encephalopathy (HIE) presents clinically with a neonatal encephalopathy (NE) whereby the mild spectrum is difficult to classify immediately after birth. For decades trials have focused exclusively on infants with moderate-severe HIE s, as these infants were easier to identify after birth and had the highest risk of adverse outcomes. Twenty years after those trials, the PRIME study finally solved the first part of the conundrum by providing a definition of mild HIE in the first 6 hours. There is strong biological plausibility and preclinical evidence supporting the efficacy of therapeutic hypothermia (TH) but there is a lack of comparative clinical data to establish the risk-benefit in mild HIE. The fundamental question of how best to manage mild HIE remains unanswered. This review will summarize (1) the evidence that neonates with mild HIE are at significant risk for adverse outcomes, (2) the gaps/controversies in management, and (3) an algorithm of care is proposed to ensure standardized management of mild HIE and the direction of future trials.

Recruitment, consent and retention of participants in randomised controlled trials: a review of trials published in the National Institute for Health Research (NIHR) Journals Library (1997-2020)

OBJECTIVES

To review the consent, recruitment and retention rates for randomised controlled trials (RCTs) funded by the UK's National Institute for Health Research (NIHR) and published in the online NIHR Journals Library between January 1997 and December 2020.

DESIGN

Comprehensive review.

SETTING

RCTs funded by the NIHR and published in the NIHR Journals Library.

DATA EXTRACTION

Information relating to the trial characteristics, sample size, recruitment and retention.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome was the recruitment rate (number of participants recruited per centre per month). Secondary outcomes were the target sample size and whether it was achieved; consent rates (percentage of eligible participants who consented and were randomised) and retention rates (percentage of randomised participants retained and assessed with valid primary outcome data).

RESULTS

This review identified 388 individual RCTs from 379 reports in the NIHR Journals Library. The final recruitment target sample size was achieved in 63% (245/388) of the RCTs. The original recruitment target was revised in 30% (118/388) of trials (downwards in 67% (79/118)). The median recruitment rate (participants per centre per month) was found to be 0.95 (IQR: 0.42-2.60); the median consent rate was 72% (IQR: 50%-88%) and the median retention rate was estimated at 88% (IQR: 80%-97%).

CONCLUSIONS

There is considerable variation in the consent, recruitment and retention rates in publicly funded RCTs. Although the majority of (6 out of 10) trials in this review achieved their final target sample; 3 out of 10 trials revised their original target sample size (downwards in 7 out of 10 trials). Investigators should bear this in mind at the planning stage of their study and not be overly optimistic about their recruitment projections.

Prostate cancer clinical trial completion: The role of geography

BACKGROUND/AIMS

One in five cancer clinical trials fails with another third failing to meet enrollment goals. Prior efforts to improve enrollment focus on patient facing interventions, but geographic factors such as regional cancer incidence may doom trials before they even begin. For these reasons, we examined associations of regional prostate cancer incidence with trial termination, and identified scientifically-underserved areas where future trials might thrive.

METHODS

We merged US phase 2-3 prostate cancer clinical trial data from ClinicalTrials.gov with prostate cancer incidence data from statecancerprofiles.cancer.gov. We matched trial information from 293 closed and 560 active trials with incidence data for 2947 counties. Using multivariable logistic regression, we identified associations with trial termination. We identified 'scientifically-underserved' counties with the highest cancer incidence quintile (>61 annual cases) but lowest active trials quintile (0 or 1 trial).

RESULTS

Of 293 closed trials, one in three was terminated (n = 96, 32.8%). On multivariable analysis, only lower regional prostate cancer incidence was associated with higher likelihood of premature trial termination (OR 0.98, 95% CI [0.96-0.99] for every 100 cases, p = 0.03). We identified 188 counties with >61 annual prostate cancer cases but 0 or 1 active trials, indicating potential scientifically-underserved areas.

CONCLUSIONS

In this novel study, we found prostate cancer trials in areas with low prostate cancer incidence were more likely to fail. We also identified scientifically-underserved areas where trials might thrive. Our findings provide a more nuanced understanding of clinical trial feasibility and upstream opportunities for improvement.

General characteristics and reasons for the discontinuation of drug clinical trials in mainland China

Background

Although discontinuation is common in clinical trials, no study has been conducted to analyse the current situation and reasons for the suspension or discontinuation of drug clinical trials in China. This study aims to analyse the general characteristics and reasons for the discontinuation of registered clinical trials in mainland China and to identify the associated factors.

Methods

We conducted a cross-sectional observational study of discontinued trials registered in the Drug Trial Registration and Information Publication Platform before March 31, 2020. All trials with a status of terminated or stopped recorded in the platform were classified as discontinued trials and included in the analysis. The basic characteristics of the discontinued trials were recorded, reasons for trial discontinuation were recorded and divided into 4 categories as drug development strategy, trial planning, trial conduct and studied drug. Pearson’s chi-square test and fisher’s exact test were used to compare the differences in reasons for discontinuation between neoplasm trials and non-neoplasm trials, and to examine the associations of trial characteristics with different reasons related to trials discontinuation.

Results

Three hundred twelve discontinued trials were included in this study. The studied drugs were mainly chemical drugs [229 (73.4%)], and indications of the studied drugs were mainly neoplasms [77 (24.7%)]. Geographical location of the discontinued trials were mostly in northern [114 (36.5%)] and eastern [96 (30.8%)] China. Study type of the included trials was mainly bioequivalence studies [97 (31.1%)]. The most common reason for trial discontinuation was commercial or strategic decision [84 (26.9%)], followed by futility/lack of efficacy [70 (22.4%)]. The number of trial centers, sample size and whether participants had been enrolled were significantly associated with trial discontinuation (P <  0.05). Multiple center trials showed a higher rate of trial discontinuation due to trial conduct related reasons than single center trials (P <  0.05), trials with sample size > 500 showed a higher rate of trial discontinuation due to studied drug related reasons (P < 0.05), and trials enrolled participants showed a lower rate of trial discontinuation due to commercial or strategic decision and a higher rate of trial discontinuation due to studied drug related reasons than trials without enrolled participants (P < 0.05). Besides, neoplasm trials showed a higher rate of trial discontinuation due to poor recruitment and safety comparing with non-neoplasm trials (P < 0.05).

Conclusions

Trial discontinuation in China mainly occurred because of commercial or strategic decision and futility/lack of efficacy of the studied drug. Clinical trials with multiple centers and a large sample size may more likely be discontinued due to trial conduct related reasons such as good clinical practice. Discontinuation due to drug safety and lack of efficacy in multiple center trials with a large sample size deserves more attention to avoid resources wastes. Full communication with regulatory authorities such as Center for Drug Evaluation and research institutes to develop a feasible protocol is important for sponsors to avoid trial discontinuation due to protocol issues.

Investigator initiated trials versus industry sponsored trials - translation of randomized controlled trials into clinical practice (IMPACT)

BACKGROUND

Healthcare decisions are ideally based on clinical trial results, published in study registries, as journal articles or summarized in secondary research articles. In this research project, we investigated the impact of academically and commercially sponsored clinical trials on medical practice by measuring the proportion of trials published and cited by systematic reviews and clinical guidelines.

METHODS

We examined 691 multicenter, randomized controlled trials that started in 2005 or later and were completed by the end of 2016. To determine whether sponsorship/funding and place of conduct influence a trial's impact, we created four sub-cohorts of investigator initiated trials (IITs) and industry sponsored trials (ISTs): 120 IITs and 171 ISTs with German contribution compared to 200 IITs and 200 ISTs without German contribution. We balanced the groups for study phase and place of conduct. German IITs were funded by the German Research Foundation (DFG), the Federal Ministry of Education and Research (BMBF), or by another non-commercial research organization. All other trials were drawn from the German Clinical Trials Register or ClinicalTrials.gov. We investigated, to what extent study characteristics were associated with publication and impact using multivariable logistic regressions.

RESULTS

For 80% of the 691 trials, results were published as result articles in a medical journal and/or study registry, 52% were cited by a systematic review, and 26% reached impact in a clinical guideline. Drug trials and larger trials were associated with a higher probability to be published and to have an impact than non-drug trials and smaller trials. Results of IITs were more often published as a journal article while results of ISTs were more often published in study registries. International ISTs less often gained impact by inclusion in systematic reviews or guidelines than IITs.

CONCLUSION

An encouraging high proportion of the clinical trials were published, and a considerable proportion gained impact on clinical practice. However, there is still room for improvement. For publishing study results, study registries have become an alternative or complement to journal articles, especially for ISTs. IITs funded by governmental bodies in Germany reached an impact that is comparable to international IITs and ISTs.

Probiotics as a treatment for prenatal maternal anxiety and depression: a double-blind randomized pilot trial

Probiotic use may be an efficacious treatment option to effectively manage symptoms of prenatal maternal anxiety and depression. Our primary aim was to test feasibility and acceptability for a probiotic randomized controlled trial (RCT) in pregnant women with pre-existing symptoms. This double-blind pilot RCT included 40 pregnant women with low-risk pregnancies and elevated depressive symptoms and/or anxiety. Once daily, participants orally consumed a probiotic (Ecologic Barrier) or a placebo, from 26 to 30 weeks gestation until delivery. A priori key progression criteria for primary outcomes were determined to decide whether or not a full RCT was feasible and acceptable. Secondary outcomes included depressive symptoms, anxiety, stress, and maternal bonding to offspring. In 19 months, 1573 women were screened; following screening, 155 women (10%) were invited for participation, of whom 135 (87%) received study information, and 40 women (30%) were included. Four out of six a priori determined criteria for success on feasibility and acceptability were met. After 8 weeks of intervention, there was no significant difference between the probiotic and placebo groups for secondary outcomes. The pilot trial was feasible and acceptable, but hampered by recruitment method and study design. Secondary endpoints did not reveal differences between the groups for improving maternal mood.

Optimizing clinical trial design using prospective cohort study data: a case study in neuro-urology

Study Design

Simulations using data from a prospective cohort study.

Objectives

To illustrate how prospective cohort data can be employed in randomized controlled trial (RCT) planning to assess feasibility and operational challenges, using TASCI (Transcutaneous tibial nerve stimulation in patients with Acute Spinal Cord Injury to prevent neurogenic detrusor overactivity: a nationwide randomized, sham-controlled, double-blind clinical trial) as a case study.

Setting

Spinal cord injury rehabilitation centers in Switzerland.

Methods

TASCI is nested in the multicenter Swiss Spinal Cord Injury Cohort Study (SwiSCI), which prospectively includes patients with acute spinal cord injury. In simulations, data from 640 patients, collected by SwiSCI, were used to investigate different scenarios of patient eligibility and study consent, as well as the performance of the randomization list. Descriptive analysis was used to describe the population of interest and the simulation results; multivariable logistic regression analysis was performed to identify predictors of discharge within the TASCI intervention time period.

Results

The recruitment target of 114 patients is obtainable within the originally envisioned three-year time period under the most favorable recruitment scenario examined. The distribution of the primary prognostic factor produced imbalance in the randomization lists and informed further discussion of the cut-off values used in stratification. Influxes of patients resulted in overlapping intervention periods for multiple participants, which guided resource allocation. Early discharge was related to the primary prognostic factor and study center, but is only anticipated in about 8% of participants.

Conclusions

Prospective cohort data are a very valuable resource for planning RCTs.

Scientometric measures of prospectively registered clinical trials over time: A comparison of IRCT and ClinicalTrials.gov

Background: Iranian Registry of Clinical Trials (IRCT) started as a primary registry in 2008. We examined the characteristics and scientometric measures of prospectively registered clinical trials in IRCT over time and compared them with that of ClinicalTrials.gov. Methods: We selected eligible trial records between 2008 and 2016 from the IRCT database. We assessed their characteristics and the journal metrics of ensuing outputs over the study period and compared our findings with the corresponding information from ClinicalTrials.gov reported by Magdalena Zwierzyna et al. and a random sample of trials registered with this registry. We used the chi-square test for comparison of proportions and Mann-Whitney U test for comparison of medians. P-value <0.05 was considered statistically significant. Statistical analyses were performed using IBM SPSS Statistics V.22. Results: 1751 prospectively registered clinical trials were eligible for analysis, of which 1526 (87%) had parallel-group design, 1541 (88%) reported to be randomized, 753 (43%) used double-blinding design, 485 (%27.7) had sample size more than 100, 1313 (75%) completed within a year, 1539 (87.9%) were single centered and 1529 (87.3%) exclusively used public money. Comparison with ClinicalTrials.gov showed that they are less likely to have multiple centers, funded by private sectors, continue beyond one year; and more likely to be randomized, double-blind and get published as a paper. The sample sizes were similar. Journal scientometric measures remained constant over the study period for both databases but were higher in ClinicalTrials.gov (median SJR=1.67, IQR=1.1-3.23) compared with IRCT (median SJR=0.58, IQR=0.34-0.91). Conclusion: Our findings suggest that clinical trials registered in IRCT are predominantly investigator-initiated studies with acceptable methodological features and high publication rate albeit in journals with substantially lower scientometric measures compared with that of ClinicalTrials.gov. Journal metric indices remained constant despite an increase in the number of registrations in IRCT.

An overview of study designs

The numbers of clinical trials have increased exponentially over the last decade, amplifying the pressure to select an appropriate study design to obtain reliable and valid evidence. The ability to find, critically appraise and use evidence to develop new interventions is fundamental to evidence-based medicine. Different study designs have their own advantages and disadvantages, and provide different evidentiary value. This article provides an overview of clinical trials, illustrating that, ultimately, the study design chosen needs to meet experimental and funding limitations, while minimising error.

A multi-state model analysis of the time from ethical approval to publication of clinical research studies

Background

Results of medical research should be made publicly available in a timely manner to enable patients and health professionals to make informed decisions about health issues. We aimed to apply a multi-state model to analyze the overall time needed to publish study results, and to examine predictors of the timing of transitions within the research process from study initiation through completion/discontinuation to eventual publication.

Methods

Using a newly developed multi-state model approach, we analysed the effect of different study-related factors on each of the transitions from study approval to eventual publication, using a data set of clinical studies approved by a German research ethics committee between 2000 and 2002.

Results

Of 917 approved studies, 806 were included in our analyses. About half of the clinical studies which began were subsequently published as full articles, and the median time from study approval to publication was 10 years. Differences across model states were apparent; several factors were predictive of the transition from study approval to completion, while funding source and collaboration were predictive of the transition from completion to publication.

Conclusions

The proposed multi-state model approach permits a more comprehensive analysis of time to publication than a simple examination of the transition from approval to publication, and thus the findings represent an advance on previous studies of this aspect of the research process.

Burden or Opportunity? Parent Experiences When Approached for Research in a Pediatric Intensive Care Unit

Despite an ongoing need for pediatric research, low study enrollment may impede study completion, particularly in critical care. We conducted a prospective cross-sectional survey and chart review study to assess parent experiences with research in a pediatric intensive care unit (PICU). Of the 80 parents who completed the study survey, 54% were approached to participate in a research study in the PICU, and 93% agreed to participate. Motivators included altruism, low burden, low risk, and research that would benefit the child. Barriers included risks to the child, the child's being too sick to participate, feeling overwhelmed, not having enough time to participate, the research's being burdensome, and the research's not being explained well. PICU parents had mostly favorable attitudes toward research participation. Compared with non-Hispanic survey respondents, respondents of Hispanic ethnicity less often reported having been approached for research, which further evidences the need to track research recruitment processes to help avoid underinclusion of members of minority populations.

Retention of Alzheimer Disease Research Participants

INTRODUCTION

Participant retention is important to maintaining statistical power, minimizing bias, and preventing scientific error in Alzheimer disease and related dementias research.

METHODS

We surveyed representative investigators from NIH-funded Alzheimer's Disease Research Centers (ADRC), querying their use of retention tactics across 12 strategies. We compared survey results to data from the National Alzheimer's Coordinating Center for each center. We used a generalized estimating equation with independent working covariance model and empirical standard errors to assess relationships between survey results and rates of retention, controlling for participant characteristics.

RESULTS

Twenty-five (83%) responding ADRCs employed an average 42 (SD=7) retention tactics. In a multivariable model that accounted for participant characteristics, the number of retention tactics used by a center was associated with participant retention (odds ratio=1.68, 95% confidence interval: 1.42, 1.98; P<0.001 for the middle compared with the lowest tertile survey scores; odds ratio=1.59, 95% confidence interval: 1.30, 1.94; P<0.001 for the highest compared with the lowest tertile survey scores) at the first follow-up visit. Participant characteristics such as normal cognition diagnosis, older age, higher education, and Caucasian race were also associated with higher retention.

CONCLUSIONS

Retention in clinical research is more likely to be achieved by employing a variety of tactics.

Publish or Perish v2

Communication of clinical trial outcomes is important, but the results of many clinical trials are never published. If we do not publish the results of clinical trials, the lessons learned from those trials will perish. The Oncologist offers a powerful solution through the Clinical Trial Results publishing platform, which uses an established template for authors to easily build a manuscript by simply providing the essential trial data. Through it, every patient's legacy of clinical trial enrollment can matter.

Intensive Triangulation of Qualitative Research and Quantitative Data to Improve Recruitment to Randomized Trials: The QuinteT Approach

Randomized controlled trials (RCTs) can provide high quality evidence about the comparative effectiveness of health care interventions, but many RCTs struggle with or fail to complete recruitment. RCTs are built on the principles of the experimental method, but their planning, conduct, and interpretation can depend on complex social, behavioral, and cultural factors that may be best understood through qualitative research. Most qualitative studies undertaken alongside RCTs involve interviews that produce data that are used in a supportive or supplicatory role, but there is potential for qualitative research to be more influential. In this article, we describe the research methods underpinning the "QuinteT" (Qualitative Research Integrated Within Trials) approach to understand and address RCT recruitment difficulties. The QuinteT Recruitment Intervention (QRI) brings together multiple qualitative strategies and quantitative data and uses triangulation to understand recruitment issues rapidly. These nuanced understandings are used to inform the implementation of collaborative actions to improve recruitment.

Discontinuation and nonpublication of interventional clinical trials conducted in patients with mild cognitive impairment and Alzheimer's disease

Introduction

Discontinuation and nonpublication of interventional clinical trials represents a waste of already scarce resources. We sought to identify the prevalence of discontinuation and nonpublication of interventional clinical trials conducted in patients afflicted by mild cognitive impairment and Alzheimer's disease.

Methods

We conducted a retrospective, cross-sectional study on mild cognitive impairment and Alzheimer's disease–based interventional clinical trials in ClinicalTrials.gov dating back to 1995. The analyzed data included trial phase, intervention type, enrollment, and funding sources. Fisher's exact and χ² tests were used to determine any potential associations between trial characteristics and completion.

Results

A total of 744 studies were identified, of which 502 (67%) were industry-sponsored ones. A total of 127 (17%) were discontinued prematurely. Of the 617 completed trials, 450 (73%) were not published, representing approximately 66,655 participants who incurred the risks of trial participation without subsequently contributing to the medical literature. Similarly, there were 18,246 patients from unpublished, discontinued trials. Of the 744 trials examined, 247 publications from 167 trials could be identified via PubMed/MEDLINE and EMBASE searches. Most notably, the odds of nonpublication among industry-sponsored trials were more than 75% higher than those in studies funded by academia (odds ratio = 1.78; 95% confidence interval, 1.14–2.78; P = .01). Furthermore, industry-sponsored trials had a 50% greater odds of study discontinuation compared with trials funded by academia (odds ratio = 1.50; 95% confidence interval, 1.04–2.16; P = .03).

Discussion

The nonpublication of many trials and preliminary results of trials that are discontinued early dilutes the quality and decreases the comprehensive nature of the medical literature. This occurs in both industry and academia. Publication of inconclusive or negative results ensures that all research activities, regardless of outcome, contribute to global medical knowledge.