AbstractModern techniques of blood collection require health screening of donors by non‐physicians using general guidelines. Health problems of concern to the donor and possible loss to future donation of actually healthy individuals are inherent in this acceptance and deferral process. Of the 108,908 donors presenting at the bloodmobiles of a regional blood center from September 1978 to February 1979, 9,542 were deferred. Of these, 1,203 with possible medical problems other than hepatitis, hypertension, or infectious disease were referred to their physician for further information concerning their suitability as donors. Over 80% had irregular pulses or histories suggestive of potential cardiovascular problems. The purpose of this study was to review the evaluation mechanism. Responses for evaluation were received from only 222 out of 1,203 (18%), and of these all but 29 (13%) were granted full permission to donate. Since only one evaluated individual with pulse or cardiovascular findings of possible significance was under the age of 35 years, this age is a reasonable cutoff for such deferrals. The minimum increase in collections with this change in deferral screening would be over 1,000 units per year in Connecticut, and perhaps 60,000 nationwid