The Declaration remained untouched until 1975, although on several occasions there were attempts or suggestions to have it revised in light of the rapid advance of medical technology. It took no time for the Council to name a special sub-committee composed of three Scandinavian doctors (Clarence Blomquist, Sweden; Erik Enger, Norway; Povl Riis, Denmark) to pursue a revision which would delineate more specifically the ideas and provide more detailed guidelines. This committee's recommendations were accepted by the 29th Assembly in Tokyo, Japan, in 1975.

Although the general focus and core ideals remained the same, the 1975 revisions were extensive: i.e., changing the terminology throughout, adding 17 new paragraphs, amending several existing points, and restructuring the document. The result of these changes was that the list of "Basic Principles" was expanded, and the following two categories (the first of which deals with research combined with therapeutic care and the second with research for purely scientific purposes) were crafted to provide guidelines more specific to those particular circumstances.

In 1983 all WMA Declarations and Statements were reviewed to ensure consistency and the use of up-to-date terminology. The Declaration of Helsinki was revised again although most of the revisions were strictly editorial in nature. The only substantive change made was the addition of a clause stating that "when a child is to be a subject for research, that minor's consent must be obtained."

In 1989, the German Medical Association expressed concern about the Declaration's Basic Principle 2 which calls for an experimental protocol to be transmitted to a "specially appointed independent committee." The German Medical Association introduced an amendment to define more clearly the appointment and status of this committee which was adopted at the Assembly in Hong Kong, in 1989.

The Declaration was again amended at the 48th Assembly in South Africa, in 1996. This time the revision represented the addition of a new sentence in order "not to exclude the use of inert placebo in studies where no proven diagnostic or therapeutic method exists.

The Declaration is now undergoing massive new revisions which will be discussed at the 52nd General Assembly in Edinburgh, Scotland in 2000.

To close this section on the Declaration of Helsinki it should be noted that this WMA document has had great impact on human experimentation and has served as a starter for establishing ethical committees in various countries to scrutinize research projects on human beings. It has been adopted not only by WMA member associations but is also recommended by the World Health Organization, and referred to by many International Laboratories, Specialty Medical Societies, the Committee of Ministers of the Council of Europe, etc.