Background: Stroke is a leading cause of death and disability in the United States. Although new treatments are being studied, most must be given early in the course of stroke to be effective. This study was performed to identify factors associated with early hospital arrival in patients with stroke. Methods: As part of the National Institute of Neurologic Disorders and Stroke Tissue-Type Plasminogen Activator Pilot Study, information from patients, patients' families, or, most commonly, the medical record was gathered on all patients presenting to the hospital within 24 hours of the onset of stroke. A total of 14 hospitals participated. Three were university hospitals, and 11 were community hospitals with and without university affiliation. The main outcome measure was the time from stroke onset to hospital arrival. Results: Of 2099 patients screened, adequate time data were available in 1159. Thirty-nine percent presented to the hospital 90 minutes or less after symptom onset and 59% within 3 hours. Early hospital arrival after stroke was greatly influenced by the type of first medical contact and, to a lesser degree, by the patient's location at the time of the stroke and the time of the day at which the stroke occurred. Hospital arrival was fastest in patients using 911 as their first medical contact (mean, 155 minutes; median, 84 minutes) vs their personal physician (mean, 379 minutes; median, 270 minutes; P<.0001) or a study hospital (mean, 333 minutes; median, 212 minutes; P<.0001). Time from symptom onset to arrival was longer for patients having the stroke at night compared with patients having a stroke in the morning (P<.05), in the afternoon (P<.01), or in the evening (P<.0001). Time to hospital arrival was significantly longer for patients having the stroke at home than for patients having the stroke at work (P<.01) or in an unknown place (P<.05). Gender, age, race, and presence of brain hemorrhage had no significant effect. Conclusions: As many as 50% of patients with stroke arrive at the hospital within 3 hours of symptom onset. Our data indicate that strategies to increase the use of 911 systems may have a high yield with regard to recruitment into urgent treatment protocols for stroke. (Arch Intern Med. 1993;153:2558-2561)