New Zealand does not have a national surveillance and monitoring system to provide high quality data on dementia. While there are some systems, such as the government Integrated Data infrastructure (IDI) (Statistics NZ, 2019) which holds linked microdata from a variety of sources, it has been shown to vastly underestimate dementia prevalence due to poor diagnostic coding and a general lack of data from both primary and secondary services (Walesby et al., 2020).

For example:

Primary care – while the expectation is that most diagnosis and management of dementia occurs in primary care, coding for dementia is not mandatory or associated with any funding so the numbers are likely undercounted.

Secondary/tertiary care – while all inpatient admissions are coded for diagnosis (including dementia), outpatient clinic diagnoses are not routinely coded so the number of those with dementia seen in older persons services (e.g., memory services, geriatric clinics, and mental health services for the elderly) is not known.

Some services such as NASC agencies capture the diagnosis of dementia as part of their interRAI assessment, but only ~10% of the 65+ population get this assessment.

Research-led institutions may gather data to investigate dementia related questions but not in a routine way.

References:

Statistics NZ. (2019). Integrated Data Infrastructure. Stats NZ website. Available from: https://www.stats.govt.nz/integrated-data/integrated-data-infrastructure/#:~:text=The%20Integrated%20Data%20Infrastructure%20(IDI,%2Dgovernment%20organisations%20(NGOs).

Walesby K., Exeter D., Gibb S., Wood P, Starr J., Russ T. (2020). Prevalence and geographical variation of dementia in New Zealand from 2012 to 2015: Brief report utilising routinely collected data within the Integrated Data Infrastructure. Australas J Ageing. https://doi.org/10.1111/ajag.12790.