What percentage of group B Rh positive donors would be expected to be crossmatch-compatible with Mr. FS?
According to probability theory, if p(A) is the probability that A will occur, and p(B) is the probability the B will occur, the probability of p(A, B) (i.e., that both A and B will occur) is calculated as:
p(A, B) = p(A) x p(B)
Put another way, the probability of two events happening together is derived by multiplying each probability.
In a Caucasian population the relevant antigen frequencies are as follows:
|Antigen||% Positive||% Negative|
The calculation for the percentage expected to be both C- and Jk(a-) is as follows:
0.33 X 0.23 = 0.076 or 7.6%