In particular, viral based gene therapy approaches have proved dangerous in past clinical trials.

A number of medicinal properties are claimed for the teasel, though not proven in medical trials:

Sculptors and medalists, proven in trials of coin design, joined this circle.

It proved its mettle in trials by shrugging off a 30mph crash into a 100-ton concrete block.

One answer, Rawson says, is to incorporate techniques that have been proved in clinical trials.

It has been proven in trials to be one of the most accurate machines of its kind, comparing well with laboratory standard equipment.

The gun proved successful in trials, but the committee thought a higher caliber gun was needed, so Armstrong built an 18-pounder on the same design.

But before any test makes its way into clinical use, she said, it must be proven in carefully designed clinical trials.

Having the status of a dietary supplement, its efficiency has not been proven in scientifically controlled and peer-reviewed trials.

And there is little debate over the strategy itself, which has largely proven itself in trials in several provinces.