This article is based on an original article in the Australian and New Zealand Journal of Public Health, authored by Annabel Begg, Lucy D’Aeth, Emma Kenagy, Chris Ambrose, Hongfang Dong and Philip J. Schluter through the Canterbury District Health Board (CDHB) in Christchurch, New Zealand
In September 2010, a series of devastating earthquakes and aftershocks rocked the Canterbury region on the east coast of New Zealand’s South Island. The most damaging single event was a magnitude 6.3 aftershock on 22 February 2011 which caused 185 deaths, the majority of which were as a result of the collapse or partial collapse of two multi-storey office buildings.
The earthquakes caused substantial damage to the region with the total construction cost of the rebuild estimated at $NZ40 billion in 2016, close to 20 per cent of New Zealand’s annual gross domestic product. Christchurch’s city centre remained cordoned off until June 2013, a total of 859 days.
Just weeks after the earthquake, the Canterbury Earthquake Recovery Authority (CERA) was established to lead and coordinate the government’s recovery efforts. When it was disbanded in 2016, a number of agencies took on responsibility for the CERA’s work, including the Canterbury District Health Board, which was delegated responsibility for ongoing social monitoring and psychosocial recovery.
Community wellbeing was recognised as being of fundamental concern throughout the post-earthquake period.
Systematic monitoring of wellbeing is important at total population level, but particularly for those parts of the population with pre-existing vulnerabilities.
The Canterbury Wellbeing Survey (CWS), a cross-sectional survey of randomly selected adults (over 18 years) living in Christchurch, was repeated biannually from April 2013 Until June 2017, and annually thereafter. Between 1,137 and 1,482 adults participated in each survey, totalling 14,100 overall.
The time series created by the CWS presents a unique opportunity to track a large, predominantly urban population as it recovers from a series of earthquakes, overall and by important sociodemographic groups. The study aims to investigate changes over time, and to ascertain whether particular subgroups carry a disproportionately heavy mental health burden relative to their peers.
The five-item World Health Organisation Well-Being Index (WHO-5) scale was introduced in April 2013, limiting this study’s timeframe from April 2013 to June 2019. The WHO-5 consists of five simple and non-invasive questions, which respondents rate according to a six-point scale ranging from 0 (at no time) to 5 (all of the time). These scores are summed and then multiplied by four to give the final score, with 0 representing the worst-imaginable wellbeing and 100 representing the best.
The disaster appeared to affect the mental wellbeing of all, and recovery was incremental and prolonged, taking a number of years. Those within the lowest household income group had lower mean WHO-5 scores than their wealthier counterparts at every measured point.
Post-disaster, Christchurch residents have had an incremental and prolonged mental wellbeing recovery, as measured by the WHO-5. This speaks to the need for the long-term monitoring of psychological consequences.
The mean WHO-5 significantly increased from 52.4 in the April 2013 survey, to 60.8 in the June 2019 survey. A significant and sustained household income group disparity existed, even when adjusting for age, gender and ethnic differences.
It was notable that females, those aged 35-49 years, and those identifying as Maori, had relatively lower mean WHO-5 scores. It has been found that the psychological wellbeing of women is more at-risk during disasters, as they are at greater risk of violence and sexual abuse, diseases and psychological trauma than men.
The large population displacement, and associated insurance claim issues disproportionately affected those in the more deprived areas – likely exacerbating the mental wellbeing demands of many Christchurch residents. In fact, many residents found the disaster itself easier to deal with than the process associated with the recovery and rebuild. This was despite government and local authorities recognising the risk of recovery processes exacerbating pre-existing inequities, and attempting to proactively mitigate against these inequities.
Community mental wellbeing recovery takes many years following a disaster, and pre-existing inequities persist despite the implementation of recovery processes aimed at mitigating these risks.
In the haste for recovery, important groups can be excluded or left behind, deepening their mental wellbeing effects. An inclusive framework that recognises and privileges the diverse needs of communities requires development and implementation if recovery is to be shared by all.
Image credit: AP Photo/New Zealand Herald, Mark Mitchell