title: Theory-based design and field-testing of an intervention to support women choosing surgery for breast cancer: BresDex.
abstract: OBJECTIVE
  Design and undertake usability and field-testing evaluation of a theory-guided decision aid (BresDex) in supporting women choosing surgery for early breast cancer.
  
  
  METHODS
  An extended Theory of Planned Behavior (TPB) and the Common Sense Model of Illness Representations (CSM) guided the design of BresDex. BresDex was evaluated and refined across 3 cycles by interviewing 6 women without personal history of breast cancer, 8 women with personal history of breast cancer who had completed treatment and 11 women newly diagnosed with breast cancer. Participants were interviewed for views on content, presentation (usability) and perceived usefulness towards deciding on treatment (utility). Framework analysis was used, guided by the extended TPB and the CSM.
  
  
  RESULTS
  BresDex was positively received in content and presentation (usability). It appeared an effective support to decision-making and useful source for further information, particularly in clarifying attitudes, social norms and perceived behavioral control, and presenting consequences of decisions (utility).
  
  
  CONCLUSIONS
  This study illustrates the potential benefit of the extended TPB and CSM in designing a decision aid to support women choosing breast cancer surgery.
  
  
  CONCLUSIONS
  BresDex could provide decision-making support and serve as an additional source of information, to complement the care received from the clinical team.
authors.affiliation: Marie Curie Palliative Care Research Group, Wales Cancer Trials Unit, School of Medicine, Cardiff University, Cardiff, UK. sivells2@cardiff.ac.uk
authors.forename: Stephanie
authors.initials: S
authors.lastname: Sivell
authors.forename: William
authors.initials: W
authors.lastname: Marsh
authors.forename: Adrian
authors.initials: A
authors.lastname: Edwards
authors.forename: Antony S R
authors.initials: AS
authors.lastname: Manstead
authors.forename: Alison
authors.initials: A
authors.lastname: Clements
authors.forename: Glyn
authors.initials: G
authors.lastname: Elwyn
mesh_terms: D000328:Adult; D000368:Aged; D001943:Breast Neoplasms / Q000523:psychology / Q000601:surgery*; D003657:Decision Making; D003661:Decision Support Techniques; D005260:Female; D006801:Humans; D033182:Intention; D007407:Interviews as Topic; D008408:Mastectomy / Q000523:psychology*; D008875:Middle Aged; D009367:Neoplasm Staging; D010358:Patient Participation; D011582:Psychological Theory; D036301:Qualitative Research; D015203:Reproducibility of Results