Is the endocrine research pipeline broken? A systematic evaluation of the Endocrine Society clinical practice guidelines and trial registration

Background: Very low quality (VLQ) evidence translates into very low confidence in the balance of risk and benefits based on the estimates drawn from the body of evidence. Consequently, this assessment highlights gaps in the research evidence, i.e. knowledge gaps, for important clinical questions. In this way, expert guideline panels identify priority knowledge gaps that, arguably, should inform the research agenda and prioritize scarce research economical resources. The extent to which the research agenda reflects the knowledge gaps identified in clinical practice guidelines is unknown. Methods: A systematic evaluation of the Endocrine Society (ES) clinical practice guidelines portfolio from 2008 to 2014 was conducted with the objectives to identify (1) recommendations in the ES clinical practice guidelines based on VLQ evidence reflecting knowledge gaps in endocrinology, and (2) active research designed to address these gaps by searching the clinical trial registry, clinicaltrials.gov, using terms describing patients (diseases), interventions, comparison, and outcomes. Results: In 25 ES guidelines, we found 660 recommendations, of which 131 (20%) were supported by VLQ evidence. Clinical trialists are attempting to answer 28 (21 %) of these knowledge gaps by performing 69 clinical trials. Conclusion: The research enterprise is addressing one in five knowledge gaps identified in clinical practice recommendations in endocrinology. These findings suggest an inefficiency in the allocation of very scarce research economical resources. Linking the research agenda to evidence gaps in clinical practice guidelines may improve both the efficiency of the research enterprise and the translation of evidence into more confident clinical practice.