The U.S. banking industry is strong enough to weather a deteriorating economy — that's the headline expected from the government when it reveals the results of its bank stress tests in the first week of May.

"We expect the stress test to demonstrate that the 19 banks are all well-capitalized even under the stress test's worst-case scenario," said Scott Talbott, senior vice president at the Financial Services Roundtable, which represents the largest financial institutions.

However, a chorus of bank analysts and economists are questioning the rigor of the stress tests if the results are really so positive. After all, just six months ago, the entire financial system was brought to its knees from the stress of capital market losses and rising mortgage defaults.

"If they come out and say all the banks are fine, no one's going to believe the test," said Christopher Whalen, managing director at analysis firm Institutional Risk Analytics.

In February, Treasury Secretary Timothy Geithner announced the Financial Stability Plan and said it would conduct a battery of tests to gauge the soundness of the nation's 19 largest banks, including Citigroup and Wells Fargo. The tests would determine if the banks have sufficient capital and could withstand a worsening recession over the next two years.

The Treasury and the Federal Reserve mapped out the worst-case scenario as an unemployment rate of over 10 percent and housing prices falling 22 percent in 2009. But they left some questions unanswered, especially if the scenario worsened.

The problem is, the stress test is based on "best guesses" of how bad the economy will get, said Michael Heller, president of Veribanc, a bank rating firm. That means that the worst-case scenario may not be pessimistic enough.

"The Treasury in May will release the amount of cushion that each bank needs in a more severe economic scenario," said Andrew Williams, a Treasury spokesman. He said the goal of the test was to "increase lending by instilling confidence in banks even if the economy worsens."

It's not like the government doesn't have a plan. Fed chief Ben Bernanke, in a testimony before the Financial Services Committee, said if any bank needed capital after the stress test, it will have six months to raise money from the private sector. Otherwise, it can request funds from the $700 billion Troubled Asset Relief Program.