The Health Services Union says the bulging $33 billion NSW health budget must be scrutinised by a royal commission because it is not reaching patients or practitioners.

A union-commissioned report entitled "Reform Critical - A Fragmented Health System at Breaking Point" accuses the state's coalition government of "chronic misallocation of resources and warped priorities".

"Some providers have incentives to provide more services to boost their incomes rather than being guided by patient health," the union said on Sunday.

The urgent call for a commission comes with around 40 days to go until the state election.

"The system is just completely out of whack," said the union's secretary Gerard Hayes.

"We can identify billions of dollars worth of spending that needs to be properly scrutinised and probably redirected to have more impact," he said.

Some of the report's key findings include that patient complaints about health services increasing by a whopping 144 per cent over the last decade and 40 per cent more since the start of the pandemic.

It said that from September 2021 to June 2022, 10 per cent of people who urgently needed an ambulance in NSW waited over two hours.

It also estimated that NSW spends $100 less per person than the Australian average, resulting in a funding shortfall of $872 million per year on services that could prevent illness and hospitalisations.

The report's authors argue the underinvestment costs the NSW hospital system over $1.1 billion per year and makes wait times worse.

Premier Dominic Perrottet has repeatedly defended his government's track record saying the state has the best health care system in the country.

But Mr Hayes said ambulance ramping and emergency wait times are "symptoms of a deeper malaise that needs to be addressed".

With nurses and paramedics going on strike over wages and lack of staffing several times last year, the report also estimates that by the end of the decade the NSW hospital sector will need an additional 25,000 full-time medical, allied health and support staff to meet projected increases in demand.

Expanding its scope to encompass a national picture, the report noted over $2.5 billion in 2021-22 was lost due to fraud in Australia's Medicare Benefits and Pharmaceutical Benefits Schemes.