Characteristics of completed clinical trials for spinal cord injury from 1999 to 2020

Compliance and factors affecting reporting of spinal stenosis and spinal-fusion-related clinical trials to ClinicalTrials.gov

INTRODUCTION

ClinicalTrials.gov is an online database that was launched in 2000 in order to help increase transparency around clinical trials. The FDA's Food and Drug Administration Amendments Act of 2007 and the subsequent Final Rule of 2016 attempted to improve compliance for reporting to the site. However, there is still significant noncompliance by researchers. This study evaluated compliance for trials related to spinal stenosis and spinal fusion.

METHODS

We utilized a previously published algorithm to predict clinical trials that were highly likely to be mandated to report. Trials found under the search criteria "Spinal Fusion OR Spinal Stenosis" and completed before June 2023 were extracted. Data was extracted from ClinicalTrials.gov on Study Status, Study Results, Interventions, Phases, Funder Type, Study Type, Study Design, Start Date, Primary Completion Date, Results First Posted and Study Locations. Additionally, the number of months between the primary completion date and the reporting of the results in the database were calculated for each study. Due to limited data points, descriptive analysis was conducted.

RESULTS

We found 86 studies that were deemed highly likely to be mandated to report. Of these trials, 13 % reported results within 12 months, and 85 % reported within 5 years. Industry (44 %) and other non-federal sources (54 %) were the primary funders, with the NIH funding none of the included studies. Median reporting times were similar across funding sources. Upon analysis, there were no factors that were significantly related to reporting in the 1-year time frame. The only significant factor for 5-year reporting was the year of study completion, with studies completed in 2016 or later showing 100 % compliance.

CONCLUSION

This study highlights improvements in reporting within 5 years since the 2016 Final Rule. However, despite regulatory efforts, there remains an increased need for reporting compliance in spinal fusion and spinal stenosis clinical trials. Continued efforts are needed to ensure increased transparency.

Time to publication for results of clinical trials

BACKGROUND

Researchers conducting trials have a responsibility to publish the results of their work in a peer-reviewed journal, and failure to do so may introduce bias that affects the accuracy of available evidence. Moreover, failure to publish results constitutes research waste.

OBJECTIVES

To systematically review research reports that followed clinical trials from their inception and their investigated publication rates and time to publication. We also aimed to assess whether certain factors influenced publication and time to publication.

SEARCH METHODS

We identified studies by searching MEDLINE, Embase, Epistemonikos, the Cochrane Methodology Register (CMR) and the database of the US Agency for Healthcare Research and Quality (AHRQ), from inception to 23 August 2023. We also checked reference lists of relevant studies and contacted experts in the field for any additional studies.

SELECTION CRITERIA

Studies were eligible if they tracked the publication of a cohort of clinical trials and contained analyses of any aspect of the publication rate or time to publication of these trials.

DATA COLLECTION AND ANALYSIS

Two review authors performed data extraction independently. We extracted data on the prevalence of publication and the time from the trial start date or completion date to publication. We also extracted data from the clinical trials included in the research reports, including country of the study's first author, area of health care, means by which the publication status of these trials were sought and the risk of bias in the trials.

MAIN RESULTS

A total of 204 research reports tracking 165,135 trials met the inclusion criteria. Just over half (53%) of these trials were published in full. The median time to publication was approximately 4.8 years from the enrolment of the first trial participant and 2.1 years from the trial completion date. Trials with positive results (i.e. statistically significant results favouring the experimental arm) were more likely to be published than those with negative or null results (OR 2.69, 95% CI 2.02 to 3.60; 19 studies), and they were published in a shorter time (adjusted HR 1.92, 95% CI 1.51 to 2.45; 4 studies). On average, trials with positive results took 2 years to publish, whereas trials with negative or null results took 2.6 years. Large trials were more likely to be published than smaller ones (adjusted OR 1.92, 95% CI 1.33 to 2.77; 11 studies), and they were published in a shorter time (adjusted HR 1.41, 95% CI 1.18 to 1.68; 7 studies). Multicentre trials were more likely to be published than single-centre trials (adjusted OR 1.20, 95% CI 1.03 to 1.40; 2 studies). We found no difference between multicentre and single-centre trials in time to publication. Trials funded by non-industry sources (e.g.governments or universities) were more likely to be published than trials funded by industry (e.g. pharmaceutical companies or for-profit organisations) (adjusted OR 2.13, 95% CI 1.82 to 2.49; 14 studies); they were also published in a shorter time (adjusted HR 1.46, 95% CI 1.15 to 1.86; 7 studies).

AUTHORS' CONCLUSIONS

Our updated review shows that trial publication is poor, with only half of all trials that are conducted being published. Factors that may make publication more likely and lead to faster publication are positive results, large sample size and being funded by non-industry sources. Differences in publication rates result in publication bias and time-lag bias that may influence findings and therefore ultimately affect treatment decisions. Systematic review authors should consider the possibility of time-lag bias when conducting a systematic review, especially when updating their review.

FUNDING

This Cochrane review had no dedicated funding.

REGISTRATION

This review combines and updates two earlier Cochrane reviews. The two protocols and previous versions of the two updated reviews are available via 10.1002/14651858.MR000006 and 10.1002/14651858.MR000006.pub3 and 10.1002/14651858.MR000011 and 10.1002/14651858.MR000011.pub2.

Comprehensive and Visualized Analysis of Interventional Clinical Trials of Spinal Cord Injury in the Past Two Decades: A Bibliometric Study

OBJECTIVE

The aim of this study was to provide a bibliometric analysis of reported clinical trials of interventional spinal cord injury (SCI) and present the current status, global trends, and scholars' knowledge in this field.

METHODS

Data were obtained from PubMed and Web of Science (WOS) Core Collection. A literature screening process was conducted to select reports of interventional SCI clinical trials. Qualitative and quantitative analysis was performed based on information from the WOS database. Co-occurrence analysis of keywords, collaboration analysis, and co-citation analysis were performed using VOSviewer.

RESULTS

A total of 849 articles were selected for analysis. Therapeutic strategies in the articles were classified into 10 subgroups. Locomotor training, local complication-related treatments, and neuromodulation are the top 3 subgroups. Spinal Cord was the most productive and most frequently cited journal in SCI clinical trials. The most productive country, institution, and author are the United States, the University of Miami, and Harvey LA, respectively. The collaboration network analysis shows that researchers and institutions from the United States, Canada, the United Kingdom, and Australia were the pivotal driving forces in this field. Spinal cord injury, rehabilitation, individuals, electrical stimulation, and exercise are the top 5 most frequent keywords. The co-citation analysis shows that the most frequently cited references are all international standards and guidelines of SCI clinical trials.

CONCLUSIONS

There is a broad research collaboration network, although it is distributed unevenly worldwide. International standards and guidelines are needed to conduct high-quality clinical trials in the future.