"Early intervention in response to difficulties can reduce the risk or severity of certain types of mental disorders later in childhood, adolescence or adulthood."
A government-ordered inquiry into mental health and addiction services is now holding public meetings around New Zealand gathering information for a report due on October 31.
Its terms of reference highlight youth as a key group for consideration.
The ministry report was based on information collected through the New Zealand Health Survey over a three-year period, using a sample of 10,457 children.
Children were assessed through a "strengths and difficulties questionnaire", an internationally used tool to chart children's development.
Boys were more likely to have concerning total difficulty scores than girls and Maori children were more likely to have concerning scores than non-Maori children.
Asian children were less likely to be experiencing difficulties than non-Asian children.
Scores were comparable for Pacific Island and non-Pacific Island children.
WHERE TO GET HELP:
If you are worried about your or someone else's mental health, the best place to get help is your GP or local mental health provider. However, if you or someone else is in danger or endangering others, call 111.
If you need to talk to someone, the following free helplines operate 24/7:
DEPRESSION HELPLINE: 0800 111 757
LIFELINE: 0800 543 354
NEED TO TALK? Call or text 1737
SAMARITANS: 0800 726 666
YOUTHLINE: 0800 376 633 or text 234
There are lots of places to get support. For others, click here.