Temporal and geographic trends in celiac disease publications: a bibliometric analysis.

BACKGROUND Despite the increasing prevalence of celiac disease (CD), the rate of diagnosis remains low. This may be related to the lack of research and publications on CD compared with other gastrointestinal conditions. We hypothesized that CD publications are underrepresented as compared with other gastrointestinal illnesses, and are particularly underrepresented in the USA. GOAL To explore the rate of CD publication output, comparing it with other gastrointestinal conditions, and to assess for changes over time. STUDY We used an iterative search process to identify all articles in PubMed from 1980 to 2009, and compared the number of publications featuring CD to Crohn's disease and Helicobacter pylori. We analyzed CD publication output with respect to its degree of diffusion among journals and authors, and assessed for an association between economic parameters and output. RESULTS The number of publications has increased steadily since 1980, with acceleration in the rate of increase beginning in 1995; this trend was also observed in the number of publications in Crohn's disease, whereas the number of publications for H. pylori has begun to decline. The 10 journals with the largest number of Crohn's disease publications were responsible for 29% of all Crohn's disease research output in 1995-1999 and 30% in 2005-2009. In contrast, the top 10 CD journals were responsible for 34% of CD output in 1995-1999, but only 25% in 2005-2009 (P<0.0001). Publication output per nation was moderately associated with gross domestic product (r=0.59, P<0.0001). CONCLUSION The number of publications in CD is increasing, out of proportion to the overall growth of the peer-reviewed medical literature. CD publications are spread throughout a larger number of journals, but are more dominated by high-volume authors. Economic factors are associated with national contributions to the world literature in CD.