title: Detection of systematic patient setup errors by portal film analysis.
authors.forename: J V
authors.initials: JV
authors.lastname: Lebesque
authors.forename: A
authors.initials: A
authors.lastname: Bel
authors.forename: J
authors.initials: J
authors.lastname: Bijhold
authors.forename: A A
authors.initials: AA
authors.lastname: Hart
mesh_terms: D006258:Head and Neck Neoplasms / Q000532:radiotherapy*; D006801:Humans; D011785:Quality Assurance, Health Care; D011878:Radiotherapy / Q000592:standards*