She said DHB's specialist service saw more than 85 per cent of referrals within three weeks and 95 per cent within eight weeks.
The specialist service encompassed Child and Adolescent Mental Health Service (CAMHS) in Tauranga and Voyagers in Whakatane.
Young people referred to CAMHS in crisis were seen straight away. Otherwise appointments were scheduled as soon as possible.
Dr Mackersey said the specialist service provided an extremely good service and referrals that were not seen within three weeks were reviewed.
When a young person was not seen within three weeks it was usually because they and their family had been unable to attend an appointment, for example due to school holidays or other commitments.
Ministry of Health senior media advisor Rebecca Walsh said young people with urgent mental health needs were seen on the same day in most instances and in all cases within 48 hours.
"For all new mental health clients, DHBs are required to meet a sector-wide target of seeing 80 per cent within three weeks, and 95 per cent within eight weeks.
"Bay of Plenty District Health Board has seen 81.3 per cent of new clients in the 0 to 19 year age group within 3 weeks, and 97.8 per cent within 8 weeks in the period from April 2015 to March 2016."
The Ministry continued to monitor performance across the mental health sector to support and work with DHBs in order to identify where improvement and additional effort is required, she said.
"Over the last four years, the number of new clients seen in the 0 to 19 years age group in under three weeks has increased by 7.2 per cent, and the number being seen in under eight weeks has increased by 4.6 percent."
During the same period, the total numbers of new clients increased from just under 13,000 to more than 15,600. These figures included over 3,000 new clients annually who were seen on the same day because of urgent need, she said.
Nationwide, 30 per cent of young people waited more than three weeks to see a provider in the year to March.
Green Party health spokesman Kevin Hague said more and more people in the community needed mental health support. For young people, that need was often urgent.
"If you think about the situation of a young person who needs assistance ... waiting three weeks is intolerable, let alone the eight weeks that some people have."
Mr Hague, who is a former DHB chief executive, said a young person waiting weeks or months for help would experience worsening mental health problems.
Where to get help:
� In an emergency: call 111
� Lifeline: 0800 543 354 (available 24/7)
� Suicide Crisis Helpline: 0508 828 865 (0508 TAUTOKO) (available 24/7)
� Youthline: 0800 376 633, or text 234 (available 24/7) or talk@youthline.co.nz or live chat (between 7pm and 11pm)
� Kidsline: 0800 543 754 (available 24/7)
� Whatsup: 0800 942 8787 (1pm to 11pm)
� Depression helpline: 0800 111 757 (available 24/7)
� Rainbow Youth: (09) 376 4155 (weekdays 11am to 5pm)
� NetSafe: 0508 NETSAFE (0508 638 723)