Rheumatoid arthritis (RA) is a chronic disease that affects synovial joints. About 1% of the world population suffers from this disease. A synovial test for the presence of the anti-citrullinated protein antibodies is commonly used when rheumatoid arthritis is suspected. This test is positive in a proportion of 67% of all RA cases and is negative 95% of the times RA is not present.
a. what is the sensitivity and the specificity of the test???
I made a table like this
present//////not present
positive 67% 5%
negative 33% 95%
sensitivity= 67%/(67%+33%)=0.67
specificity=95%/(95%+5%)=0.95
am I on the right track???