title: How patient referral bias can confuse interpretation of clinical results: elective lymph node dissections at the Sydney Melanoma Unit.
authors.forename: C M
authors.initials: CM
authors.lastname: Balch
mesh_terms: D002986:Clinical Trials as Topic / Q000379:methods*; D006801:Humans; D008197:Lymph Node Excision; D008545:Melanoma / Q000473:pathology / Q000601:surgery*; D012189:Retrospective Studies; D015983:Selection Bias; D012878:Skin Neoplasms / Q000473:pathology / Q000601:surgery*