These are individuals:
- who are registered in the BIG-register (a register of professions in individual health care), who practise as a dentist (without registered specialty) or as a doctor in combination with a registered medical specialty (including general practice), excluding social-medical specialties,
- whose only source of income from labour is profit from own enterprise,
- and who work in health care or a health care-related sector. This means that the group not only includes doctors who treat patients themselves, although this is the case for the large majority.
Doctors with a private company and doctors who have an employee contract alongside their independent practice are not included in the study. The figures for 2009 are based on tax declarations of 4.5 thousand medical specialists, 6.9 thousand GPs, and 4.7 thousand dentists.