; for the SpecTRA Study Group IMPORTANCE Sex differences have been described in the presentation, care, and outcomes among people with acute ischemic strokes, but these differences are less understood for minor ischemic cerebrovascular events. The present study hypothesized that, compared with men, women are more likely to report nonfocal symptoms and to receive a stroke mimic diagnosis. OBJECTIVE To evaluate sex differences in the symptoms, diagnoses, and outcomes of patients with acute transient or minor neurologic events. DESIGN, SETTING, AND PARTICIPANTS This prospective cohort study of patients with minor ischemic cerebrovascular events or stroke mimics enrolled at multicenter academic emergency departments in Canada between December 2013 and March 2017 and followed up for 90 days is a substudy of SpecTRA (Spectrometry for Transient Ischemic Attack Rapid Assessment). In total, 1729 consecutive consenting patients with acute transient or minor neurologic symptoms were referred for neurologic evaluation; 66 patients were excluded for protocol violation (n = 46) or diagnosis of transient global amnesia (n = 20). EXPOSURES The main exposure was female or male sex. MAIN OUTCOMES AND MEASURES The main outcome was the clinical diagnosis (cerebral ischemia vs stroke mimic). Secondary outcomes were 90-day stroke recurrence and 90-day composite outcome of stroke, myocardial infarction, or death. The association between presenting symptoms (focal vs nonfocal) and clinical diagnosis was also assessed. Research hypotheses were formulated after data collection. RESULTS Of 1648 patients included, 770 (46.7%) were women, the median (interquartile range) age was 70 (59-80) years, 1509 patients (91.6%) underwent brain magnetic resonance imaging, and 1582 patients (96.0%) completed the 90-day follow-up. Women (522 of 770 [67.8%]) were less likely than men (674 of 878 [76.8%]) to receive a diagnosis of cerebral ischemia (adjusted risk ratio [aRR], 0.88; 95% CI, 0.82-0.95), but the 90-day stroke recurrence outcome (aRR, 0.90; 95% CI, 0.48-1.66) and 90-day composite outcome (aRR, 0.86; 95% CI, 0.54-1.32) were similar for men and women. No significant sex differences were found for presenting symptoms. Compared with patients with no focal neurologic symptoms, those with focal and nonfocal symptoms were more likely to receive a diagnosis of cerebral ischemia (aRR, 1.28; 95% CI, 1.15-1.39), but the risk was highest among patients with focal symptoms only (aRR, 1.45; 95% CI, 1.34-1.53). Sex did not modify these associations. CONCLUSIONS AND RELEVANCE The results of the present study suggest that, despite similar presenting symptoms among men and women, women may be more likely to receive a diagnosis of stroke mimic, but they may not have a lower risk than men of subsequent vascular events, indicating potentially missed opportunities for prevention of vascular events among women.