[Epidemiological factors in allergic rhinitis. Review and personal comparative study of rural and urban populations in the province of Barcelona].

After a bibliographical perusal of the subject, the AA. deals with the main epidemic factors of allergic rhinitis such as frequency, age, sex, race, geographical differences, climatic and seasonal influences, social and economic status, date of birth, duration, links with asthma bronchial and other allergies, etc. The contribution of the AA. is the personal comparative investigation done, during a 3 years period in rural and urban populations of the province of Barcelona.