title: Geographic variation in the intended choice of adjuvant treatments for women diagnosed with screen-detected breast cancer in Queensland.
abstract: BACKGROUND
  Although early diagnosis and improved treatment can reduce breast cancer mortality, there still appears to be a geographic differential in patient outcomes. This study aims to determine and quantify spatial inequalities in intended adjuvant (radio-, chemo- and hormonal) therapy usage among women with screen-detected breast cancer in Queensland, Australia.
  
  
  METHODS
  Linked population-based datasets from BreastScreen Queensland and the Queensland Cancer Registry during 1997-2008 for women aged 40-89 years were used. We adopted a Bayesian shared spatial component model to evaluate the relative intended use of each adjuvant therapy across 478 areas as well as common spatial patterns between treatments.
  
  
  RESULTS
  Women living closer to a cancer treatment facility were more likely to intend to use adjuvant therapy. This was particularly marked for radiotherapy when travel time to the closest radiation facility was 4 + h (OR =0.41, 95 % CrI: [0.23, 0.74]) compared to <1 h. The shared spatial effect increased towards the centres with concentrations of radiotherapy facilities, in north-east (Townsville) and south-east (Brisbane) regions of Queensland. Moreover, the presence of residual shared spatial effects indicates that there are other unmeasured geographical barriers influencing women's treatment choices.
  
  
  CONCLUSIONS
  This highlights the need to identify the additional barriers that impact on treatment intentions among women diagnosed with screen-detected breast cancer, particularly for those women living further away from cancer treatment centers.
authors.affiliation: Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia. j2.hsieh@hdr.qut.edu.au.
authors.forename: Jeff Ching-Fu
authors.initials: JC
authors.lastname: Hsieh
authors.affiliation: Cancer Research Centre, Cancer Council Queensland, Brisbane, Queensland, Australia. SusannaCramb@cancerqld.org.au.
authors.forename: Susanna M
authors.initials: SM
authors.lastname: Cramb
authors.affiliation: Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia. james.mcgree@qut.edu.au.
authors.forename: James M
authors.initials: JM
authors.lastname: McGree
authors.affiliation: Preventive Health Unit, Department of Health, Brisbane, Queensland, Australia. Nathan.Dunn@health.qld.gov.au.
authors.forename: Nathan A M
authors.initials: NA
authors.lastname: Dunn
authors.affiliation: Cancer Research Centre, Cancer Council Queensland, Brisbane, Queensland, Australia. PeterBaade@cancerqld.org.au.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Baade
authors.affiliation: Mathematical Sciences, Queensland University of Technology, Brisbane, Queensland, Australia. k.mengersen@qut.edu.au.
authors.forename: Kerrie L
authors.initials: KL
authors.lastname: Mengersen
mesh_terms: D000276:Adjuvants, Immunologic; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001315:Australia; D001499:Bayes Theorem; D001943:Breast Neoplasms / Q000175:diagnosis / Q000628:therapy*; D002755:Choice Behavior; D055088:Early Detection of Cancer; D005260:Female; D006297:Health Services Accessibility; D006728:Hormones / Q000627:therapeutic use; D006801:Humans; D033182:Intention; D008875:Middle Aged; D011793:Queensland; D018714:Radiotherapy, Adjuvant; D012959:Socioeconomic Factors
chemical_list: D000276:Adjuvants, Immunologic; D006728:Hormones