The icons in this chapter 'populations' are used in two ways. First, the reader should sometimes be informed about specific populations, or differences between populations (e.g. the differences in volume of distribution between adults and elderly).

Second, sometimes the location at a specific part of the body is necessary for a proper understanding of the illustration. In that case, a whole body or merely a part of the body is shown (like the reference to the 'big toe' in case of gout). For a better understanding, please note that the skin tone and gender is kept 'neutral' (blue) to indicate that it concerns 'humans' in general, unless specified otherwise.