I must get down to a controlled study of this.

Few if any controlled studies have been carried out to answer the question.

At a certain point, he decided to begin a controlled scientific study.

Results are always better in a controlled initial study than when they go out for general use.

Only those women participating in controlled studies can get them now.

We see it as an open door to doing more controlled studies at the university.

Limited controlled studies are available due to its recent invention.

Evaluation by controlled studies needs to be built into the legislation.

Although it's not a controlled study, it gives one pause.

In fact, one of the few controlled human studies inspired more debate than answers.