Analyzing conflicts between Clinical Trials from a patient perspective

Patients with serious long-term disease often search for clinical trial information on their own, using sites such as ClinicalTrials.gov. We are developing a patient-focused search tool for clinical trials. Since patients are often concerned that participation in one clinical trial may preclude their participation in other trials, one of the planned features of this system will be the ability to analyze whether treatments in one trial will prevent a patient from participating in another. This paper describes an approach to this task. Eligibility criteria are classified according to linguistic pattern, UMLS concepts, content, and time. The criteria are then compared with treatments and side effects in other trials relevant to a patient, in order to identify potential conflicts.