Publication Rates of Registered Clinical Trials in Diabetic Macular Edema

Introduction: To determine the publication rate of registered clinical trials evaluating therapeutic approaches for diabetic macular edema (DME). Methods: Using the search terms “Diabetic Macular Edema,” the National Institute of Health’s ClinicalTrials.gov online registry was searched to identify all clinical trials concerning DME. Non-interventional trials, terminated trials, trials not concerning DME, and those not completed between 2005 and 2015 were excluded. Publication status of each trial was determined using searches of the study title, keywords, author(s), and NCT number on PubMed.gov and Google Scholar. Results: A total of two hundred and forty-seven studies were identified in the primary analysis. Of the 97 trials meeting inclusion criteria, 60 (61.9%) were published. Late-phase trials were published at higher rate (74.5% [35/47]) than early phase trials (50% [25/50]) (p = 0.01). Trial location, date of completion, and industry involvement did not significantly affect the publication rate. Conclusion: Of the registered trials listed in the ClinicalTrials.gov registry investigating DME, 61.9% were published.