It has not been shown in controlled clinical trials to be effective, and costs over $7,000.

Updated results of the population based controlled trial in Germany.

If nothing else, a controlled trial needs a hypothesis to test.

There have been no controlled trials so the optimal treatment is not known.

The review noted that a large controlled trial "may no longer be ethical."

We would demand to see the data from a controlled trial.

Only a controlled clinical trial could answer that question, he added.

As of 2011, it is being investigated in controlled clinical trials.

We are now moving on to the next phase, a controlled trial late this year or in early 2006.

This was not a controlled trial but a retrospective assessment of the patients seen over the previous seven years.