Outcome Measures in Study Registries: The Need for a Consistent Approach

The definition of outcome measures is the core part of a clinical study protocol and is also key information when posting the protocol and results information from a study on registries like https://doi.org/ClinicalTrials.gov . Unfortunately, there are some differences in terminology and language used in study protocols and study registries. At first glance, these discrepancies might not appear to be that important, but they have the potential to introduce critical inconsistencies. In this article, we give an overview of definitions and issues in this area, report about the harmonization efforts under the Clinical Data Interchange Standards Consortium (CDISC) and Health Level Seven (HL7) initiatives, and provide a SMART principle to improve the definition for outcome measures. For clear communication and interpretation of the study information, we need a common language that harmonizes the terminology between the study protocol and the information posted on different study registries to avoid serious misunderstandings as well as wrong conclusions.