The three immediate causes of stroke are cervical carotid artery disease, atrial fibrillation and hypertension. Recognition and appropriate management of these causes can prevent the majority of strokes they would have caused, The purpose of this study was to develop a new protocol for screening for these causes that is more accurate, rapid and cost effective than existing protocols. In this protocol, rather than relying on auscultation with a stethoscope, the carotid artery was screened with a newly developed and more accurate quick color image scan ultrasound technique and a lead 2 EKG rhythm strip was used to find atrial fibrillation, The focus in this protocol was on the rapid detection of the three immediate causes of stroke and did not include a lengthy questionnaire or long counseling. A cholesterol determination was not included and there was little or no cost to the participants. In stroke screening trials of the new protocol at two institutions, 176 participants were screened at a rate of one every 2.7 minutes, There were 26 with > 50% carotid stenosis, 16 with previously unknown cardiac arrhythmias and 104 had hypertension, It was concluded that this protocol provides an accurate, rapid and cost-effective means of screening for the three immediate causes of stroke and can on broad application result in significant stroke reduction. (C) 1998 The International Society for Cardiovascular Surgery, Published by Elsevier Science Ltd. All rights reserved.