please help!

Centers for Disease Control http://www.cdc.gov/

Medline Plus from the National Institiues for Health http://www.nlm.nih.gov/medlineplus/medlineplus.html

PubMed from the National Library of Medicine http://www.ncbi.nlm.nih.gov/pubmed

Nursing Center for various nursing journals http://www.nursingcenter.com/home/index.asp

I hope these help.

What is your research paper about? Usually there is some sort of Academy, Association, etc for each disease or condition. Those are credible, but not always the most informational websites. For example if it is something that affects children you can refer to the American Academy of Pediatrics. There is an American Academy for nearly everything!

Basically anything that isn't from About dot com or Wikipedia dot com or from some sort of forum is considered credible. You just have to make sure that the information didn't come from an article written by Joe Schmoe for some website that nobody has ever heard of.