Background and Purpose—Reliable comparisons of stroke incidence are important. To determine the impact of systematic
assessment of patients referred with transient ischemic attack on the measured incidence and severity of stroke, we
compared 2 population-based studies.
Methods—Patients with first-ever stroke ascertained during 2006 through 2010 from the Dijon Stroke Registry and the
Oxford Vascular (OXVASC) Study were studied. Both studies comply with the criteria for ideal incidence studies, but
the OXVASC Study also systematically assessed all patients referred with transient ischemic attack. Stroke severity was
measured by the National Institutes of Health Stroke Scale.
Results—Among 902 incident strokes in Dijon and 748 cases in the OXVASC Study, age and gender distribution were
comparable, but severity was lower in the OXVASC Study (median National Institutes of Health Stroke Scale, 2 versus 6;
P