The report has not been made public but has been seen by the BBC.
It found that untrained staff were carrying out risky restraints on patients and that the number of restraints was high.
It said face-down, and particularly face down in a prone position, are the highest tariff interventions of physical restraint, and the most dangerous techniques to deploy.
The report looked at a sample of 40 cases and found more than half were patients being restrained face down on the floor for longer than 30 minutes.
The longest restraint was one hour and 45 minutes.
“That is completely against all guidelines,” Prof Tyrer said.
“You may have to do things for five minutes or up to 10 minutes but to go beyond 40 minutes there is something badly wrong in the organisation of a unit if that is allowed to continue.”
Carseview is a hospital to care for patients with mental illness from depression and anxiety to schizophrenia and psychosis.
In July last year, BBC Scotland broadcast allegations by patients of bullying by staff, illegal drug-taking and being pinned to the floor unnecessarily.
Experts called it abusive and said the unit should be closed down.
NHS Tayside responded by commissioning an internal report into Carseview to go alongside independent reports into mental health in Tayside.
The internal report says a whistleblower has come forward and accused Carseview of “very serious concerns over leadership, safety and malpractice”.
It came up with 11 recommended actions including urgent action on staff training and critical action on illegal drugs on the ward.
It said the restraint policy should emphasise the safety of patients as well as staff and that the culture of the unit should be “based around the caring and compassionate leadership approach”.
NHS Tayside said the recommendations covering patient care and culture were “now being progressed”.
Prof Peter Stonebridge, acting medical director for NHS Tayside, said a “steering group has been established” to focus on restrictive care practices, including the reduction of face-down restraint.
Joy Duxbury, professor of mental health at Manchester Metropolitan University, told BBC Scotland: “I think this is a terribly toxic environment.
“The figures on physical restraint are exceptionally worrying.
“These are very vulnerable clients who are being restrained, in my view, unnecessarily and by far too many staff in too many situations.
“For me, given what we know about psychological and physical trauma of the use of restraint in such setting, this is of significant concern.”
Marnie Stirling, who had two stays in Carseview with anxiety and depression, spoke to the BBC documentary last year.
Reacting to the report, she said: “If you think about mental health, it’s supposed to be about recovery. This isn’t recovery, it’s further punishment for people.”
David Fong spent a month in the unit after experiencing psychosis in 2013.
He claimed staff used restraint violently and repeatedly during his time there.
His mother Lorraine said: “This is a total and utter disgrace that this has gone on for seven years and maybe longer.”
David told BBC Scotland that staff were quick to see frustration and anger arising from detainment as aggression.
“Staff are too keen to initiate restraint and offer little or no de-escalation when no actual aggression has been displayed by the patient,” he said.
“I ask how many of these restraints were actually needed and if some are instigated by staff rather than patients?
“I personally was physically assaulted with the application of intense pain through twisting of arms, wrists and fingers or a member of staff’s knee being dug into my back, had my face rubbed into the floor causing loss of skin from my face, and had verbal abuse screamed at me during restraint.
“I also could not have been the only patient that these tactics were being used upon.”
A separate report looking at the patient experiences came up with separate 23 recommendations in December.
It is feeding into an independent inquiry, which was announced in the Scottish Parliament last year, and is still ongoing.
Suicide rates in Dundee are higher than any other city council area in Scotland, according to a new report.
The Scottish Suicide Information Database also shows that men accounted for three-quarters of suicides across Tayside in the last seven years.
According to the report, there were 164 deaths caused by suicide in Dundee with an average of 16.7 per 100,000 population between 2011 and 2017.
Angus along with Perth and Kinross Councils recorded 98 and 126 suicides respectively.
For Tayside as a whole, 388 suicides were recorded with an average per 100,000 population of 14.1.
Men were more likely to take their own lives, with the rates across Scotland highest among those aged 35-54 and in deprived areas.
Nearly three-quarters of those who died had contact with healthcare services in the year before their death.
An inquiry is currently under way into NHS Tayside’s mental health services after a number of concerns surrounding the Carseview Centre.
Phil Welsh, whose 28-year-old son Lee took his own life last year, said the latest statistics were “damning”.
He said: “It’s clear that there’s a situation here that isn’t working.
“I think the fact there is an inquiry shows there’s something amiss.
“Mental health is a discussion point now but it’s all well talking, we need support for people afterwards and that is why we badly need a crisis centre.”
A spokeswoman from NHS Health Scotland said: “National suicide prevention programmes need to incorporate a comprehensive public health approach which seeks to reduce stigma, improve mental wellbeing in the whole population and address the underlying causes of poor mental health.”
Bosses at the health board aim to get rid of 1,300 posts to plug the hole in its finances, official papers revealed.
They say they can do that over several years through “natural staff turnover”, but it is feared cuts to backroom staffing will have an impact on patients.
The decision to shrink the workforce comes as the board benefits from having at least £62 million of debt written off by the Scottish Government.
The plans are revealed in an assurance report to the board from September.
It said there was an “acceptance that staff levels need to reduce by 10%”.
Gillian Murray, who has been campaigning for better mental health services after failings in the care of her late uncle, said the decision shows that “balancing the books obviously means more to them than saving lives”.
“People in Dundee are dying because NHS Tayside is a shambles and to cut the workforce is another slap in the face for all of us,” she added.
Murdo Fraser, the Conservative MSP in Perthshire, said: “Local people will be wondering what impact these massive reductions in staff will have on their already pressured services.”
Annie Ingram, NHS Tayside director of workforce, said no one will lose their job but said spending on the workforce is higher than health boards of a similar size.
She added: “We are carrying out a review of staff numbers, grades and skills, which is being carried out in partnership with our staff and our trades unions, to ensure we have a safe, affordable and sustainable workforce.”
The NHS in Scotland is not financially sustainable and its performance has continued to decline, the public spending watchdog has warned.
Audit Scotland said health boards were “struggling to break even” and none had met all of the key national targets – with NHS Lothian not meeting any.
It highlighted increasing demand on NHS services, and rising waiting lists.
Health Secretary Jeane Freeman said the government was already taking forward Audit Scotland’s recommendations.
But the watchdog’s report prompted widespread criticism of the Scottish government, with the Conservatives claiming it should “make shameful reading for the SNP”.
The report said pressure is building in several areas – including the recruitment and retention of staff, rising drug costs, Brexit and a significant maintenance backlog.
It said “decisive action” was needed to protect the “vital and valued service”.‘
What does the report say?
The report warned that the NHS in Scotland is “not in a financially sustainable position”, with NHS boards “struggling to break even, relying increasingly on Scottish government loans and one-off savings”.
And it said the “declining performance against national standards indicates the stress NHS boards are under”.
The only target met nationally in 2017/18 was for drugs and patients to be seen within three weeks.
Only three of Scotland’s regional health boards met the target for patients beginning cancer treatment within 62 days of being referred
The proportion of youngsters seen by CAMHS within 18 weeks fell from 83.6% in 2016/17 to 71.2% in 2017/18.
The Scottish government invested £13.1bn in NHS services last year, but Audit Scotland said when inflation was taken into account there was a 0.2% real terms drop in cash.
Health boards made “unprecedented” savings of £449.1m, but many relied heavily on one-off savings for this, while three boards – NHS Ayrshire and Arran, NHS Highland and NHS Tayside – needed £50.7 million of loan funding from the government to break even.
This was “significantly more” than in previous years, with Audit Scotland saying four boards have predicted they will need a combined total of £70.9m in this current financial year.
The report said the “NHS is managing to maintain the overall quality of care, but it is coming under increasing pressure”, adding Brexit would create “additional challenges” for the health service.
However the scale of these challenges was “difficult to assess” because of “significant uncertainty” over the terms of the UK’s withdrawal deal from the European Union, and because data on workforce nationality is not routinely collected.
Auditor General Caroline Gardner said: “The performance of the NHS continues to decline, while demands on the service from Scotland’s ageing population are growing.
“The solutions lie in changing how healthcare is accessed and delivered, but progress is too slow.”
What has the Scottish government said in response?
Health Secretary Jeane Freeman said the government was already taking forward Audit Scotland’s recommendations.
She said NHS funding had reached “record levels of more than £13bn this year, supporting substantial increases in frontline NHS staffing, as well as increases in patient satisfaction, reductions in mortality rates, falls in healthcare associated infections, and Scotland’s A&E performance has been the best across the UK for more than three years.”
She added: “While our NHS faces challenges, common with health systems across the world, we are implementing a new waiting times improvement plan to direct £850m of investment over the next three years to deliver substantial and sustainable improvements to performance, and significantly improve the experience of patients waiting to be seen or treated.
“Ultimately we want to ensure people can continue to look forward to a healthier future with access to a health and social care system that continues to deliver the world-class compassionate care Scotland is known for.”
What other reaction has there been?
Conservative health spokesman Miles Briggs claimed the NHS was “facing an unprecedented challenge” with boards across the country “staring into a black hole of more than £130m.
He said: “For a government which has been in charge for more than 11 years, this should make shameful reading for the SNP.”
Labour’s Monica Lennon added: “After more than a decade of SNP complacency our NHS is in crisis.”
Dr Lewis Morrison, chairman of the British Medical Association (BMA) in Scotland, said the “stark warning” from Audit Scotland “could not be any blunter”.
But he added this would “come as no surprise to frontline doctors who have faced the consequences of inadequate funding year after year”.
And RCN Scotland director Theresa Fyffe said the report “underlines what those in the nursing profession have been warning about for a number of years – an unsustainable pressure on staff to deliver more care.
“This leads to staff burnout and, in some cases, a choice between staying in the profession and their own health.”