Europe still hasn’t regained investor confidence in its banks.

The European Central Bank’s stress tests of the region’s lenders failed to provide an accurate gauge of their financial stability, according to 51% of respondents to the latest quarterly poll of investors, traders and analysts who are Bloomberg subscribers. The results were viewed as accurate by 32% of the people who responded, while 17% said they weren’t sure.

The tests followed three previous efforts by another European regulator that were deemed unreliable after some banks that passed collapsed a few months later. Investors expected the ECB to take a tougher approach before it took over as the single supervisor of eurozone banks this month. While 25 of the 130 institutions failed the ECB’s test, an even smaller subset was asked to raise $8bn of capital.

“We’ve improved the banks with some more capital and more transparency, but it wasn’t good enough,” said Michael Nicoletos, managing director of Athens-based AppleTree Capital, which oversees about $45mn of investments. He participated in last week’s Bloomberg Global Poll. “I’m sure there are some banks that are in worse shape than they appeared in the test.”

Fifty-six percent of poll respondents said regulators haven’t done enough to prevent another financial crisis in Europe, while 30% said they had done enough and 14% said they weren’t sure.

“Regulators never look forward,” said Florin Bota-Avram, a trader at Cluj-Napoca, Romania-based Banca Transilvania who participated in the poll. “They want to prevent the future crisis by looking at the past, but the future is always different than the past.”

The poll of 510 Bloomberg customers was conducted on November 11 and 12 by Selzer & Co, a Des Moines, Iowa-based firm. It has a margin of error of plus or minus 4.3 percentage points.

US regulators used stress tests to restore confidence in the banking system in 2009 after the collapse of Lehman Brothers Holdings. The 10 banks that failed that first test were asked to raise $75bn. They ended up selling $100bn of new shares within a few weeks to strengthen their balance sheets. The US has been conducting tests every year since, forcing the weakest banks to cancel plans to increase dividends or buy back shares so they build capital instead.

Poll respondents were more positive on the US stress tests. Forty-six percent said the US exams provided an accurate gauge of banks’ financial stability, versus 36% who disagreed. Similarly, 48% of the respondents said US regulators had done enough to prevent another crisis while 42% said they hadn’t.

Authorities on both sides of the Atlantic have passed new laws since Lehman Brothers’s collapse to strengthen the financial system. The US has gone further than the European Union in some instances, such as in restricting the leverage of the biggest lenders. Those efforts haven’t convinced everyone that banks will survive the next meltdown.

“When the next debt crisis hits, and it will soon, all banks won’t survive that,” said James Shugg, a senior economist based in London for Australia’s Westpac Banking Corp “Depending on how deep and severe the next crisis is, you will see more banks fail.”

Meanwhile, the ECB plans to inspect the internal models that banks use to calculate their risks to ensure that these systems behave consistently, a senior policymaker said yesterday.

Regulators have had in-house computer models in their sights in the wake of the financial crisis due to concerns some banks may attempt to downplay the riskiness of their assets and hold less capital than they should.

The ECB, which took over as the eurozone’s leading financial regulator in November, aims to compare these models using regional data and look for inconsistencies, ECB Executive Board member Sabine Lautenschlaeger said at a conference in Frankfurt.

Lautenschlaeger’s comments referred to the way banks use financial models to assess the risks they are taking in the market.

The ECB’s attention to these models is part of a wider push to impose order on the sector, which could lead to changes in the way banks do business.

“The ECB will use its position as a supervisor to gain an in-depth understanding of internal model issues and exploit its cross-sectional overview of some of the world’s largest banks to address any inconsistencies in a very direct way,” Lautenschlaeger said.

“In next two or three years we will look into every model,” she said.

The ECB is also charged with regularly checking that banks have viable business models, something that has not been done consistently in all the eurozone states.

A top ECB regulator said on Monday the central bank would be intrusive when it checks banks’ business models in its first year as Europe’s most powerful banking regulator.