Figure 2

Database contents summary. A. Instances per relationship type. B. Instances per Age Ontology age class. An instance is assigned the most specific Age Ontology class which contains the whole of the age range to which that instance is linked. The age ranges of each class are as follows: Infant new born: 0-1 month; Infant: 0-2 years; Child: 2-12 years; Preschool child: 2-6 years; Adolescent: 12-18 years; Adult: 18-120 years; Young adult: 18-24 years; Middle aged: 45-64 years; Aged: 64-120 years; 80 years or over: 80-120.