Now there are calls for rigorous tests to be introduced.

Every hypothesis is just waiting for a more rigorous test to knock it down.

Of these, only the three mentioned had been able to pass the rigorous tests for space flight.

But very few such rigorous tests are done on beauty supplements, he said.

Whatever happens, Landry said, he and his wife expect to put the new technology to a rigorous test.

The two companies share the cost of a more rigorous test than either company would do on its own.

Every week we carry out around 15,000 rigorous tests on water samples.

The Brown study has given that hypothesis its most rigorous test.

The testing service has been criticized in recent years for not making its test rigorous enough.

There is therefore much to be learned from a more rigorous test - performance in action.