Food sensitivity was confirmed in three patients on double blind challenge.

Five patients who consistently identified particular foods as causing symptoms did not have double blind challenges.

The second ace of his career came at the fifth hole and helped fend off a double Spanish challenge.

Compared to other workers, organization attempts on the behalf of farm-workers face a double challenge.

Singers in recital have a double challenge when it comes to memory: notes plus words.

The West as a whole, and not just Europe, faces a double political challenge from religion today.

When both parents work, it's a double challenge.

Secondly, we voted against the single currency because of a double challenge to democracy.

"Many whites don't understand the double challenge many of us face," he said.

Learning differences pose a double challenge: identification and then proper remediation.