Objective: To quantitatively investigate the history of medical pharmacy research by pharmacists in Japan, original article titles from the Japanese Journal of Pharmaceutical Health Care and Sciences (Jpn J Pharm Health Care Sci) and the Journal of Japanese Society of Hospital Pharmacists (JJSHP) were analyzed by text-mining.
Method: The titles of all original articles (2,611 and 2,260 articles) published in Jpn J Pharm Health Care Sci and JJSHP between 1975 and 2009 were collected from article databases and analyzed using KH Coder, the free software for quantitative text analysis of the Japanese language.  KH Coder extracts basic text information data by counting the occurrence rate of certain words.  Article titles were assigned to nine research categories according to coding rules, and the categorization results were analyzed quantitatively.
Results: Between 1975 and 1989, “pharmaceutical investigation” was the major area of research in the Jpn J Pharm Health Care Sci.  Articles assigned to the category “drug therapy” gradually increased through the 1990s and, since 2000, “drug therapy” has dominated medical pharmacy research.  In the JJSHP between 1975 and 2004, no characteristic research area was found, and mainly research articles directly related to pharmacist practice were published.  However, from 2005 to 2009, articles assigned to the “drug therapy” category accounted for 34% of all published articles making “drug therapy” the major research area in the JJSHP.  Thus, in recent years, there is no obvious difference in research areas between the two journals.
Conclusion: Our analyses suggest that drug therapy research is now at the center of medical pharmacy research by pharmacists in Japan.