Blood culture contam rate

[John Gentile]

I'm a little embarrassed to post this, but since I've been out of the micro
lab for just about 2 years now I am realizing that I'm losing my expertise
in the lab. :(

Our micro supervisor just retired and I've been given the technical
oversight for the lab. I need to report to the IC committee on the blood
culture contamination rate. I've collected the data of which ones seem to be
contaminants, but I can't locate the formula to calculate the rate.

I want to separate the numbers into total number of cultures, total number
of true pos cultures and total number of contaminated cultures. Is the
contam rate then the #of contam cult / # of total cultures? Or is it the
number of contam cult / number of true pos?

Thanks for your help - I couldn't find it in the ASM manual. I know I have
read about it recently, but just can't locate the info.

-- 
John Gentile                            President,  Rhode Island Apple Group
yjgent at cox.net                      RIAG Web page:  www.wbwip.com/riag/
"I never make mistakes, I only have unexpected learning opportunities!"