Michael Bland stresses that ICAMHS and crisis support is available for those acutely unwell or those at risk to themselves or others.
"Assessments for autism or ADHD can be a 10-hour body of work for a single client, including working with parents, siblings, and usually these are school-age children and we'll be working with their schools," he said.
Autism New Zealand spokesperson Larah van der Meer said these wait times were typical of those across the country and were likely to have implications for health outcomes.
"For years Autism NZ has heard from people that obtaining a diagnosis through the public system involves lengthy waitlists, and that costs for diagnosis in private practice are prohibitively high," said van der Meer.
In research undertaken by the advocacy and education group early last year, wait times were found to be particularly long for children seeking diagnosis over adults. Nationally the average wait time for an autism diagnosis for a child sits at 10.9 months, while for adults that timeframe drops to 4.8 months.
"The slow process is likely due to demand for autism diagnostic services being considerably higher than the available resources to meet the need," said Bland.
A private assessment for autism could cost up to $1449.00, while the cost of an ADHD assessment sits around $1152.50 in Nelson.
Bland said the sector was in desperate need of clinical psychologists to address wait times.
"The workforce has been difficult over the last year," he said.
He told Local Democracy Reporting that hope was on the way for those on the waitlist, with a co-design strategy approach in the works, looking to the broader portfolio of services for children and young people experiencing mental health issues.
"That waitlist will reduce when we get our workforce capacity managed," he said.
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