title: Mail surveys of general practice physicians: response rates and non-response bias.
authors.forename: James
authors.initials: J
authors.lastname: Young
mesh_terms: D015982:Bias; D006801:Humans; D010821:Physicians, Family / Q000706:statistics & numerical data*; D011177:Postal Service; D011795:Surveys and Questionnaires; D013557:Switzerland