1. Confusing volume with results. This is a case of confusing output research with outcome research. A huge pile of press clippings may document effort, but the pile does not document that the clippings had an effect.
2. Substituting estimation for measurement. Public relations practitioners should not substitute intuition or approximations for objective measurement—guesswork has no place in evaluation research (or any research).
3. Using unrepresentative samples. Analyzing only volunteer or convenience samples may lead to errors.
4. Confounding knowledge and attitudes. It is possible that a public might have gained more knowledge as the result of a public relations campaign, but this increased knowledge does not necessarily mean that attitudes have been positively influenced.
5. Confusing attitudes with behavior. Similar to item 4, it is incorrect to assume that favorable attitudes will result in favorable behavior.