This paper sought to determine how well the ‘ever-Māori’ method corrects for the undercount of Māori in routinely collected health databases in New Zealand for estimating trends in fatal and serious non-fatal injury incidence. The study authors compared trends in frequencies and age-standardised rates for fatal injury indicators with the use of: (a) ever-Māori classification; (b) New Zealand Census Mortality Study adjustment ratios applied to Total Māori counts from the Mortality Collection; and (c) Total Māori counts from the Mortality Collection. For serious non-fatal injury, trends using ever-Māori were compared with Total Māori from hospital discharge data. Analyses found that while the absolute number of injuries attributable to Māori varied depending on the method used to adjust for ethnicity status, trends over time were comparable.
