#75 The Fate of Prospective Spine Studies Posted on ClinicalTrials.gov

General Session: Quality of Spine Care

Presented by: D. Ohnmeiss


D.D. Ohnmeiss (1)

(1) Texas Back Institute Research Foundation, Plano, TX, USA


Introduction: There has been concern expressed about research ethics with respect to withholding results of clinical studies. One site available for all clinical trials is ClinicalTrials.gov. The original purpose of this site was to facilitate patients seeking a trial for the treatment of their particular condition. The internationally available site offers general information about the study, sponsor name, principal investigator, patients selection criteria, enrollment goal, study design, outcome measures, participating centers, initiation date, date posted, date completed, and other pertinent data. The site can be used to identify studies conducted for a particular condition or intervention. The purpose of this study was to investigate the fate of spine-related studies posted on ClinicalTrials.gov, with particular focus on the publication rate of completed trials.

Methods: Multiple searches were conducted on ClinicalTrials.gov website to identify studies related to commonly treated spinal conditions including herniated disc, degenerative disc disease, stenosis, and spondylolisthesis. Studies related to tumors, fractures, or that included non-spine conditions were not included. For studies classified as completed more than 18 months prior to this review, literature searches were conducted to determine if the results of the study had been published and factors related to publication.

Results: There were 263 spine-related studies identified from searches on the ClinicalTrials.gov site. Data on the site had the studies classified as follows: 72 completed, 70 active, not recruiting (generally indicates collecting follow-up data), 74 recruiting, 11 recruiting by invitation, 13 not yet recruiting, 18 terminated, 4 withdrawn, and 1 suspended. Among the 72 classified as completed, further analysis found that only 21 were posted prior to initiation or shortly thereafter. Studies posted retrospectively were not included in this analysis to determine the publication rate, as there was a potential for bias in deciding to post a study after completion or many months after initiation. Among the 21 completed trials, 8 (38.1%) have been published. One additional study was recently completed and may have not yet completed the review/publication cycle. The mean time to publish was 2.1 years from the date of completion. Among unpublished studies, the mean length of time from study completion to the preparation of this abstract was 2.2 years. There was no difference in likelihood of publication based on the country of study origin. Industrial sponsored research was less often published than studies with other sources of support.

Discussion: While the 38.1% publication rate for spine-related studies found in this study appears low, it is in line with other studies reporting a 22.8% publication rate for arthroplasty trials (Smith et al. J Arthroplasty, 2012) and 43.2% for orthopaedic trauma trials (Gandhi et al., BMC Musculoskeletal Disord, 2011). In addition to ClinicalTrials.gov website fulfilling its original goal of providing patients information about clinical studies, it can also provide a means of tracking publication of prospective studies, changes to protocols, matching publication content to posted study design, etc. and raise queries concerning the reasons for not publishing what appear to be well-designed studies. The posting of spine studies prior to initiation can increase transparency and ability to evaluate clinical trials in spine.