A deeper analysis in thyroid research: A meta-epidemiological study of the American Thyroid Association clinical guidelines

Background: The American Thyroid Association (ATA) uses the GRADE or the American College of Physicians (ACP) system to develop recommendations. Recommendations based on low-quality evidence should spur for the conduction of clinical studies, if feasible. The extent to which recommendations by the ATA based on low-quality of evidence are being actively researched remains unknown. Methods: Clinical guidelines produced by the ATA using the GRADE or the ACP system to classify evidence were deemed eligible. Reviewers, in duplicate and independently, extracted therapeutic recommendations based on low-quality evidence, whereas recommendations with higher quality of evidence, aimed at diagnosis, or best practice statements were excluded. Eligible recommendations based on low-quality evidence were deconstructed to their components using the PICO format. We then searched on clinicaltrials.gov to identify ongoing research. Trials were deemed eligible if they addressed the PICO question with at least one of the intended outcomes. Results: A total of 543 recommendations were retrieved, of which 305 (56%) were based on low-quality of evidence and only 90 were deemed eligible. Of these, we found that 33 (37%) recommendations were actively being researched in 53 clinical trials. Most of the trials were randomized and funded by non-profit organizations. Many clinical trials studied thyroid nodules and differentiated thyroid cancer (26/53; 49%), whereas few studied were aimed at anaplastic thyroid cancer (2/53; 4%). Conclusion: One out of three of gaps in evidence, identified as low quality during the development of ATA guidelines, are currently actively researched. This finding calls for the need to develop a better research infrastructure and funding to support thyroid research.