Persons – aged 15 to 69 years – with a university doctorate degree (PhD). The figures in this study are based on a three-year average over 2004, 2005 and 2006. As the study was conducted in the context of an international project, and international comparability is therefore important, the age bracket used here differs from the one usually applied at Statistics Netherlands. Statistics Netherlands uses the age bracket 15 to 64 years for the labour force, for example.

Statistics Netherlands publishes annually the number of people awarded a PhD in the year concerned,  by sex and discipline.