In this summary, we reviewed Japanese large databases available as pharmacoepidemiology data sources. In addition to the National Claims Database, two commercially available insurance claims databases are widely used: Japan Medical Data Center(JMCD) and JammNet.Three large pharmacy claims databases are also reviewed.The pharmacy claims database has unique characteristics in Japan because a prescription is valid only for four days and therefore the prescription records are believed to be almost identical to the dispensing records. Two large hospital-based databases are also available.In order to properly use these databases for the pharmacoepidemiological research questions, we need to learn first the medical practice and medical systems in Japan to have a better understanding for data source and data items. Automated large databases can be a powerful tool for pharmacoepidemiology studies by learning strengths and limitations of each database. (Jpn J Pharmacoepidemiol 2012; 17(2): 135-144)

Background :There have been only a few comparative observational studies on the safety and effectiveness of drugs in Japan. Comparative observational studies would provide important information to address these issues and thus we need to establish a means to facilitate such studies. In comparative studies, it is important to prevent the distortion of results due to selection bias. Though we do not yet have a claims database for use in pharmacoepidemiological studies, recently many hospitals and pharmacies have computerized prescription data which may be used to minimize selection bias. Good standardized procedures for the identification of patients prescribed one of two or more drugs to compare in a study using computerized prescription data would serve as a basis for a variety of pharmacoepidemiological studies in Japan.
Methods :We carried out a questionnaire survey in 2753 hospitals and 909 community pharmacies to estimate the fraction of hospitals where computerized data can be used to identify all eligible patients who used a specific drug.
Results :Questionnaires were returned by 1942 (71%) of 2753 hospitals and 632 (70%) of 909 pharmacies. From among those which responded, patients were identified, the patient list was printed, and the electronic file of the patient list was generated in 75%, 64% and 36% of the 1942 hospitals and in 100%, 93% and 49% of the 632 pharmacies respectively.
Conclusion :With procedures using computerized prescription data, the cohort for observational comparative studies may be identified with a minimal selection bias in a majority of hospitals and pharmacies.

Here we report the results of a long-term analytical study on the utilization of antihypertensive and antibacterial agents, which was performed using the Integrated Medical Information System (IMIS) developed by Kochi Medical School. The results indicate clear (increasing or decreasing) patterns in the numbers of patients and the dosages. Specifically, the total amount of antibacterials recently prescribed is significantly lower than in the year analysis began (1983). This reduction provides evidence of a steady improvement in the quality of medication and is particularly important for macrocosmic evaluation of the primary focus of our study, which was the “proper use of drugs”. Furthermore, the results also showed medication prescribed by non-specialists to be less inventive than that prescribed by specialists. This study highlights the importance of reforming institutions providing medical treatment from the perspective of effectively utilizing medical resources (by employing specialist personnel) and the proper use of medications. Because non-specialists prescribe medication in numerous medical facilities throughout Japan, these issues must be seriously considered.

For the purpose of pharmacists to be able to be more involved clinically, the pharmacy education system in Japan was revised in April 2006 and the term length of pharmacy education was extended from 4 years to 6 years.
The Japanese Society for Pharmacoepidemiology is deeply concerned about the new curriculum which will be adopted for the 6-year course, especially the handling of pharmacoepidemiology education. Two questionnaire surveys were sent to the dean of all schools of pharmacy to inquire whether they lecture pharmacoepidemiology and, if not, what study in pharmaceutical sciences would be most closely related to pharmacoepidemiology. The surveys were conducted just before and just after the introduction of the new system, in October 2005 and July 2007. The recovery of the first and second survey were 90% and 76%, respectively.
In the first survey only 17 universities (31%) had lectures on pharmacoepidemiology but in the second survey 31 universities (57%) did, and in 55% of these 31 universities the lecture was required. The result indicates that the understanding of professors of pharmacy school regarding the lecture have been gradually promoted and they feel that pharmacoepidemiology is going to be considered to be one of the essential lectures in pharmacy education in Japan. However, many responders indicated that pharmacoepidemiology was still an immature field of study and there are few appropriate textbooks and no teaching experts, and therefore, the society should take these matters into reconsideration.

  In 2008, Japanese Society of Drug Informatics (JASDI) organized the Future Vision Committee (the Committee) to propose the essential focus of drug informatics.  To explore a future vision about the drug information sciences, it was necessary to collect a variety of opinions widely from researchers.  Therefore, at the 11^th annual meeting of JASDI in July 5-6, 2008, the Committee convened a workshop to extract problems in the researches of drug informatics by using KJ method and evaluated the contents.  The major problems raised were “the field of drug informatics is too broad” and “there is no definition and/or no system of the drug informatics”.  Related problems raised are the shortness of the history and lack of originality in the study.  From different viewpoints, it was also pointed out that the methodology of the research is not well established and no systematic education is provided.  Taken together, major problems in drug informatics are concluded to be the lack of definition and the lack of systematizations, and will be solved to a certain extent by defining the outcome of the researches in drug informatics.