Incidence of asthma in female Swedish hairdressers.
OBJECTIVE: To investigate the risk of asthma in hairdressers. METHODS: The incidence of asthma was retrospectively estimated in a Swedish nationwide study including all female hairdressers certified from vocational schools from 1970 to 1995, and a stratified sample of women from the general population were referents. A postal questionnaire included questions on respiratory tract symptoms, atopy, s