[pjreddie]

http://en.wikipedia.org/wiki/Ignaz_Semmelweis

> Despite various publications of results where hand-washing reduced mortality to below 1%, Semmelweis's observations conflicted with the established scientific and medical opinions of the time and his ideas were rejected by the medical community. Some doctors were offended at the suggestion that they should wash their hands and Semmelweis could offer no acceptable scientific explanation for his findings.

He published a lot on the subject and was rejected because it didn't fit in with how doctors saw the world and he had no theory to back up his findings. It wasn't until Pasteur that germ theory gained any widespread acceptance so it's pretty irrelevant that other people thought of it first.

Plenty of things are evaluated in controlled studies and still rejected today. For example, the article that you presumably just read discusses one such thing.