ONE in three patients seeking mental health treatment at WA emergency departments last year waited more than eight hours to be seen.

In the wake of the Ellenbrook murders, mental health lobby group Consumers of Mental Health WA said statistics revealed WA was the worst-performing State for response times to people presenting to emergency departments for mental health reasons.

CoMHWA chief executive Shauna Gaebler said the snapshot, compiled by the Australasian College for Emergency Medicine, revealed about 74 per cent of people in WA who attended at hospital for mental health reasons were not admitted.

About 8 per cent of those gave up waiting and went home.

“People who end up in emergency for mental health reasons are waiting for unacceptably long periods,” Ms Gaebler said.

“We are calling for immediate action to improve how emergency departments respond to people with mental health needs.”

Teancum Vernon Petersen-Crofts, who is accused of killing his mother Michelle Petersen, 48, brother Rua, eight, and sister Bella, 15, at their Ellenbrook home on Sunday, was remanded for a mental health assessment after facing a Midland court.

It is understood that less than 24 hours before the alleged murders, Mr Petersen-Crofts, 19, was in an agitated state at Midland public hospital’s emergency department.

The Weekend West has been told he was calm before he left hospital.

Mental Health Minister Roger Cook could not comment on the Ellenbrook case but said West Australians had access to outstanding mental health services.

“Mental health will always be a challenge for our community,” he said. “It’s continuing to grow as a challenge.”

Mr Cook said mental health accounted for only 3.8 per cent of all emergency department presentations.

“Mental health patients who arrive at EDs are admitted based on clinical need to the first available bed,” he said.

Among other available services is the Mental Health Emergency Response Line, a 24-hour call centre that provides advice and referral services to anyone involved in a mental health emergency.

This includes people who feel they need urgent assistance such as families or carers of those with a mental illness or members of the public who witness a mental health crisis.

“MHERL is staffed by highly skilled specialist clinicians who triage all calls and determine appropriate treatment pathways based on the triage assessment,” an East Metropolitan Health Service spokeswoman said. “Treatment pathways for callers can include referral to other mental health services, and provision of advice or information about how to access support.”

In 2015-16 MHERL received 6593 calls with that figure jumping to 7468 in the following 12 months. Between July and November last year there were almost 4000 calls to MHERL.