Background: Time is essential for the treatment of acute stroke. Much time is lost outside the hospital, either due to failure in identifying stroke symptoms or due to a delay in notification or transport. We review studies reporting factors associated with better stroke knowledge and shorter time delays. We summarise the evidences for the effect of stroke knowledge and education on people's reaction in the acute situation of stroke.
Methods: We searched MEDLINE for studies reporting factors associated with prehospital time of stroke patients, or knowledge of stroke symptoms. Further, we searched for studies reporting educational interventions aimed at increasing stroke symptom knowledge in the population.
Findings: We included a total of 182 studies. Surprisingly, those factors associated with better stroke knowledge such as education and sociodemographic variables were not related to shorter time delays. Few studies report shorter time delays or better stroke knowledge in persons having suffered a previous stroke. Factors associated with shorter time delays were more severe stroke and symptoms regarded as serious, but not better knowledge about the most frequent symptoms such as hemiparesis or disorders of speech. Only 25-56% of patients recognised their own symptoms as stroke. While stroke education increases the knowledge of warning signs, a few population studies measured the impact of education on time delays; in such studies, time delays decreased after education. This may partly be mediated by better organisation of EMS and hospitals.
Interpretation: There is a discrepancy between theoretical stroke knowledge and the reaction in an acute situation. Help-seeking behaviour is more dependent on the perceived severity of symptoms than on symptom knowledge. Bystanders play an important role in the decision to call for help and should be included in stroke education. Education is effective and should be culturally adapted and presented in a social context. It is unclear which educational concept is best suited to enhance symptom recognition in the acute situation of stroke, especially in view of discrepancies between knowledge and action.