Australia is explicitly ignoring the inhumane treatment of refugees held on Nauru as a means of deterring others from attempting the journey to Australia, two peak rights groups have found after visiting the island.

Amnesty International, working in conjunction with Human Rights Watch, travelled to and documented the conditions for asylum seekers and refugees in Australian-funded detention on Nauru over the past few months.

They were forced to send investigators incognito after a number of requests for official visits were rebuffed or ignored.

Human Rights Watch senior counsel Michael Bochenek entered Nauru in July without telling the Government of his role with the association.

"Driving adult and even child refugees to the breaking point with sustained abuse appears to be one of Australia's aims on Nauru," Mr Bochenek said in the report.

Titled Australia: Appalling abuse, neglect of refugees on Nauru, the joint report details what are now familiar concerns about mental health, access to adequate medical care, attacks from the local Nauruan population, and concerns for the education and health of the 49 children on the island.

The Amnesty and HRW researchers, who visited the island separately, spoke to more than 80 of the 1,200 people forcibly transferred and detained on Nauru after seeking asylum in Australia.

Most have been recognised as refugees and live in the community, yet Amnesty researcher Anna Neistat told the ABC they suffer.

Over 400 asylum seekers and refugees remain in cramped tents on Nauru. ( Supplied: Amnesty International )

"What I found on Nauru is what I can only describe as a deliberate, systematic abuse," she said.

"We're not talking about individual cases, we're talking about patterns, and I think it is quite clear — and in fact I don't think the Australian Government tried very hard to hide it — that essentially they are making an example to prevent further arrivals by boat."

The organisations said the report will now be used as part of a global campaign to have Nauru closed and those transferred there resettled.

"It's an Australian Government-run operation, whatever they may say, and so ... the Australian Government has the primary responsibility," Mr Bochenek said.

Successive Australian governments have supported the policy, which they say is needed to stop people drowning at sea during dangerous boat journeys.

An Immigration Department spokesman told the ABC that as the department was not consulted about the investigation, it had had no opportunity to inform itself of the report's claims.

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Listen Duration: 3 minutes 11 seconds 3 m 11 s AM speaks with Nauru report's authors Download 5.8 MB

It said it would strongly encourage the authors to contact the department before airing allegations of the kind made in the report.

Broadspectrum, which provides services at the detention facilities on Nauru, said it had yet to see the report.

International Health and Medical Services, the main medical service provider, rejected the allegations when asked for comment, Amnesty and HRW said.

Detention 'designed to make people give up'

Temperatures in tents regularly reach 45 to 50 degrees Celsius. ( Supplied: Amnesty International )

Opposition immigration spokesman Shayne Neumann said Labor, which was responsible for reopening the centre in 2012, was "deeply troubled" by the report.

In a statement, Mr Neumann said Immigration Minister Peter Dutton needed to "immediately investigate these claims".

"This is an Australian Government funded facility and the culture of secrecy cannot be allowed to continue," he said.

Further comment has been sought.

Sorry, this video has expired The World's Beverley O'Connor speaks to former Nauru magistrate Peter Law

Senator Sarah Hanson-Young said the Greens would push for new laws to "ensure transparency and media across to all of Australia's detention camps" when Parliament returns later this month.

In a statement to the ABC, Senator Hanson-Young said Prime Minister Malcolm Turnbull needed to take action on the situation in Nauru.

"The entire regime of detention on Nauru is designed to be cruel, designed to make people to give up on seeking asylum and go home, even if that is back to war in Syria or torture in Iran," she said.

"When I was on Nauru it was clear that the conditions were unacceptable and were only going to get worse.

"The Government has known for well over a year that women in particular are unsafe and that rape and sexual assault by local men is prevalent, yet [Immigration] Minister [Peter] Dutton has wilfully turned a blind eye."

Specialised medical equipment and staff are not available on the island, and refugees and asylum seekers report long delays in receiving treatment for serious conditions. ( Supplied: Amnesty International )

ABC/Reuters