Nonlinear behavior of search strategies for identifying relevant orthodontic articles.

The communication process with electronic literature databases permitting a freetext search is prone in part to nonlinear, chaotic behavior. Even very minor changes in the initial conditions (search query) have a dramatic impact on the concluding event (search outcome). This statement has been verified with reference to alterations to the term "orthodontic" in search strategies of published systematic reviews. The results showed that a variation in one letter led to an average of 152 papers, 81% of them of orthodontic relevance, failing to be localized. Yet, the opposite effect, the elimination of papers (-418), was also observed, confirming the underlying nonlinear pattern. Search queries for orthodontic articles should invariably be equipped with the robust truncation "orthodon*." Truncation variants of key words should be used as a matter of principle to verify the outcome.