RESUMO
We studied the demographic, laboratory, and operational parameters that might influence individual, as well as average, plateletpheresis yields. Multivariate linear regression analyses showed that 25.4% and 11.6% of variability, among males and females, respectively, in individual yields was explained by the platelet count prior to that donation and 55% of the variation in mean platelet yields (PYs) was explained by the pre-first donation platelet count, the first donation PY and the body mass index (BMI). Logistic regression analysis showed that donors with first donation PYs higher, compared to those with lower yields, than the median of all mean PYs were more likely to be relatively high platelet yielders over the long term. A statistically significant, although clinically insignificant, decline in predonation platelet counts is seen in all donors regardless of the total number of donations or interdonation interval. Donors with high pre-first donation platelet counts, first donation yields, and BMI are likely to be consistent good platelet yielders.