I found it just looking on google but it seems to be a pretty reliable study from what I could tell. Here is the link in case you'd like to take a look. http://www.medscape.com/viewarticle/569721
The best advice I can offer you is to trust what you are being told by your Dr's. I would consider what they are telling you to much more reliable than some random article you read on the internet. Some, in fact many of the things you will read are not from sources I would call reliable.
I always caution people from "surfing" the internet by means of gathering information. Alot of what you find are reports on very rare incidences and again can the source of the report be reliable. This can be very misleading to you, leaving you to believe that you are in danger when your Dr has told you otherwise.
Out of curiosity, where did you find this study published?