Each individual represented in the data is allocated to a single ethnic group, using the following priority system: Māori > Pacific peoples > Indian > Asian (excl. Indian) > Other > European. Individuals of European and of Other ethnicities are often grouped together and presented as being part of the 'European or Other' ethnic group due to small numbers in the 'Other' ethnic group.
Deprivation is derived according to the residence of the individual. Deprivation scores are based on the 2006 New Zealand Deprivation Index for people giving birth before 2010 and on the 2013 Deprivation Index for people giving birth from 2010 onwards.
Deprivation quintiles are based on the area of residence for the woman or baby. They range from 1 (least deprived) to 5 (most deprived), according to the 2006 New Zealand Deprivation Index. Approximately equal numbers of the population reside in areas associated with each of the five deprivation quintile areas.
This publication uses prioritised ethnicity, whereby each person represented in the data is allocated to a single ethnic group using the priority system Māori > Pacific peoples > Asian > European > Other. The aim of prioritisation is to ensure that where it is necessary to assign people to a single ethnic group, ethnic groups that are small or important in terms of policy are not swamped by the European ethnic group.
While the data is collected for 'women' it is important to note that it actually includes all people who have given birth and that the data may include some transgender people.