Analysing clinical trial outcomes in trial registries: towards creating an ontology of clinical trial outcomes

A clinical trial is a study that evaluates the effects of one or several interventions on a certain population regarding some outcomes - variables that are monitored to assess the impact of the intervention. Trial outcomes are one of the crucial characteristics of a clinical trial. Outcomes are defined by several aspects, such as the name of the variable monitored, measurement tool used, timepoints, analysis metric, aggregation method. We propose to semi-automatically create a structured database of trial outcomes and aspects defining them, that can be used as support for outcome extraction task or to the development of Core Outcome Sets (COS). We propose to use the data from trial registries – online databases containing information about planned and conducted clinical trials, including outcomes. We apply supervised and unsupervised Natural Language Processing techniques to describe and analyse trial outcomes extracted from registries.