effectiveness

noun3

1. •
   The property of being effective, of achieving results.

   • The effectiveness of the drug was well established.
2. •
   The capacity or potential for achieving results.

   • The problem with these precedents is that the Security Council did not authorize intervention in Syria, and an intervention there will thus harm, not help, the Council’s credibility and effectiveness. — 2013
3. •
   The degree to which something achieves results.

   • He questioned the effectiveness of the treatment.