Design of a prospective cohort study to assess ethnic inequalities in patient safety in hospital care using mixed methods

Table 1 Ethnic background classification

Dutch ethnic origin	A patient is classified as ‘Dutch’ when the patient and one or both parents of the patient were born in the Netherlands, or when the patient was born outside the Netherlands while both parents were born in the Netherlands.
Non-Western ethnic origin	A patient is classified as ‘non-Western’ when the patient and one or both parents of the patient were born in a non-Western country^a, or when both parents were born in a non-western country, irrespective of the country of birth of the patient.
Classification of country of origin for non-western patients	When a patient and one or both parents were born in the same country, e.g. Turkey, that country is the country of origin, the patient will be classified as ‘Turkish’. When both parents of the patient were born in the same country, which is different from the country of birth of the patient, the country of birth of both parents is the country of origin. When a patient and his/her parents were born in three different countries, the country of birth of the mother will indicate the country of origin of the patient.
	An exception exists for our ethnic origin definition regarding Javanese Surinamese patients who were born in Suriname and whose both parents were born in Indonesia. According to the CBS definition they would be classified as “western”. But they are included in our non-western study sample and classified as Javanese Surinamese.

^a Non-Western countries are: Turkey, all countries in Africa, all countries in South America, and all countries in Asia except Japan and Indonesia.