SNOMED CT can be used to assist the process of identifying clinical trial candidates for recruitment into formal clinical trials. Subsets of findings, procedures or medications (see section 6.1 Subsets) can be used to filter trial candidates based on their clinical conditions or treatments. Subsumption techniques (see section 6.2 Subsumption) can be used to identify suitable candidates, irrespective of the level of granularity in which their clinical data is stored. SNOMED CT defining relationships (see section 6.3 Using Defining Relationships) can be used in a number of ways – for example, identifying patients with diseases of specific anatomical sites, with certain morphologies; patients who are taking medications with specific ingredients or dose forms; and patients who have had procedures on a specific body site.
Commercial tools, which can be used to support clinical research include Cerner's clinical research module (PowerTrials), which offers patient identification functionality (case study 12.2.7 Cerner).