A Review of Research Studies Using Data from the Administrative Claims Databases in Japan

Background In Japan, several research studies have used administrative claims databases. However, no study has compared the studies conducted in each database. Objective We assessed the type, design, and research area of each research study using the administrative databases in Japan to illustrate the suitability of the database used for the types of research studies. Methods We reviewed studies from four administrative claims databases (the Japanese National Database of Health Insurance Claims and Specific Health Checkups [NDB]; the DPC Study Group database [DPC]; Japan Medical Data Center [JMDC]; and Medical Data Vision [MDV]). The PubMed database was searched from January 2015 to October 2020. We assessed the type, design, and research area of the abstract or full text of each research study. Results Overall, 643 studies were included. The number of studies increased from 59 in 2015 to 171 in 2020. Descriptive studies accounted for 62.7% (42 studies) of the studies from the NDB, while the treatment effectiveness studies accounted for 81.7% (211 studies) of the studies from the DPC database and were the most common in the JMDC and MDV. Cohort studies accounted for only 17.9% of the studies on NDB but 45.5% on DPC. The most common research area was medicine, general, and internal medicine (53 studies, 8.4%). Conclusions The type and design of the studies conducted differed in each database and were influenced by the characteristics of the database used. In the future, it may be necessary to integrate various real-world data databases to increase their comprehensiveness.