It would be interesting to see the actual reserach methodology used to identify these results. I have several questions as to the accuracy of such findings:

It may be true that it is difficult under laboratory conditions to prove that a link exists between wearing a copper bracelet and perceived benefits of the wearer, but, not long ago medicine recommended the application of radioactive creams ( Marie Curie) , and denied any link between smoking and cancer.
Because the link is not scientifically verifiable dose not mean it does not exist. I would leave the decision as to whether copper bracelets have a benefit to the person wearing them.