Japan's contribution to research on infectious disease

We explored the degree of Japan's contribution to research in the field of infectious disease in the last decade. Articles published from 1991-2000 in highly reputed journals on infectious disease were accessed through the MEDLINE database. The number of articles having an affiliation with a Japanese institution was counted in total and for the respective journals. The proportions of randomized controlled trials (RCTs), case-control/cohort studies, and case reports among the articles affiliated with Japan were also calculated, and were compared with the overall proportions of these types of articles for all articles published in these journals. Japan's contribution to research on infectious disease was 3.4% of the total articles and ranked sixth among all countries. The recent trend in contribution was negative, although not statistically significant (P=0.19). RCTs in total articles published in these journals were 3.9%, which proportion has been increasing significantly over time. On the other hand, only one RCT (0.2%) was reported from Japan in the last decade. In addition, the proportion of case-control/cohort studies (2.2%) was smaller for articles from Japan than those from other countries. Compared with those of other developed countries, Japan's contribution to research on infectious disease has been unsatisfactory in the last decade. An explanation for this phenomenon should be determined and remedial measures should be taken forthwith.