The International Lists of Causes of Death and Diseases underwent their Fourth and Fifth Revisions during the years before the First and Second World Wars, the only time that two institutions of different disciplines, the International Statistical Institute and the League of Nations Health Organization, participated in the revision process. This resulted in a mixture of institutional rivalry and cooperation, involving national, ideological and professional interests.

The revisions entailed extensive international discussions. The studies on which they were based revealed a lack of international uniformity in disease classification and thus basic problems regarding the reliability and comparability of vital statistical data.