Using Savicevic as a representative of the European views on andragogy (though this is too narrow an approach for broader studies because their are five European schools of thought on the discipline of andragogy), the emphasis is to research the origin and development of education and learning in adults as these are expressed in all their manifold expressions, implying the inclusion of informal as well as formal learning and education.
The American emphasis is on the bifurcated (dual) pathway of andragogy, which is the process of acquiring learning in the adult mind and the process of making that learning available to the adult:
The learning theory and the design theory. The learning theory is based upon the adult and her/his desire to become and/or to express themselves as a capable human being, and it has six components. ... The design theory is based in a process, and is not dependent upon a body of content, but helps the learner acquire whatever content is needed. There are eight components of the design process....