Background: Varied use of terminology around a common theme creates barriers to communication and presents obstacles to systematic literature retrieval. Concepts such as baseline risk and prognosis may be expressed in a variety of ways depending on the context including time, geographic region, and research discipline. Bias may be introduced into systematic reviews on methods andepidemiology topics if search terms used do not include all the possible ways of conceptualizing the topic. Conversely, inclusion of terms whose meanings vary depending on the context will impact the specificity of a search.

Objective: Explore the context distribution and potential impact of different health concept terminology in peer-reviewed literature using the examples of baseline risk and prognosis concepts.

Methods: For each concept, MEDLINE citations and the full-text of general medical and specialty journals will be searched using a set of terms identified from the literature and by consulting experts. Frequency of use for each term will be assessed in different contexts. Additionally, MEDLINE search results will be semantically analyzed to plot the frequency of citations containing the terms of interest across time, region, and discipline. Context analysis of term usage within full text and citations will be conducted using text mining of a corpus identified by the searches.

Results: An initial search related to the concept of baseline risk (including absolute risk, overall prognosis, natural history, etc.) showed that the relative frequency of terms vary depending on the journal. Semantic analysis of MEDLINE citation results also found discipline-specific term preference. Prognosis-related terms will be searched to assess terminology variability around another complex concept.

Conclusions: The use of terms varies between disciplines and regions of practice. Complete results including context analysis and impact will be presented.