Newman and Roth developed models for predicting the probability of adverse reactions in blood donors. These can help identify a donor who may require closer monitoring during and after the blood donation. The authors are from Wayne State University, American Red Cross Blood Services and Pfizer Pharmaceutical Corporation.


Model for any donor reaction:

(1) body weight in pounds

(2) age in years

(3) number of previous donations


Number of Previous Donations


none (first time)


1 or more



X =

= (-0.0162 * ((body weight) - 110)) - (0.0208 * ((age in years) - 17)) + (0.499 * (points for number of previous donations)) - 1.415


probability of a donor reaction =

= 1 / (1 + EXP((-1) * X))


The maximum risk for an adverse reaction is around 29%, which is seen in a 17 year old first time donor weighing 110 lbs. The minimum risk is seen an old, heavy multiple donor.


Additional models were prepared to predict the risk for:

(1) fatigue after the donation (higher risk in low weight females)

(2) soreness in the arm used for the donation (higher risk in a thin, young female)

(3) bruise at the venipuncture site (higher in Caucasian females)


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