Evidence proving its effectiveness is still lacking but it continues to be a popular activity.
Experiments to prove the therapy's effectiveness in humans have yet to be done.
But the agency refused, saying the company had not proved the drug's effectiveness.
Weaver says people want to work more in order to prove their effectiveness.
The company says it did not set out to do a scientific study that would have proved its effectiveness.
If such a protein is found, much work would still be needed to prove its effectiveness for a vaccine.
The technology will also help magazines in trying to prove their effectiveness as marketing vehicles.
There is still a long way to go to prove the treatment's effectiveness, however.
You are right to raise this point and it is one way for our legal systems to prove their effectiveness.
This system has proved its effectiveness over many years.