Sharing decisions in breast cancer care: Development of the Decision Analysis System for Oncology (DAS-O) to identify shared decision making during treatment consultations.
BACKGROUND
Shared Decision Making (SDM) is widely accepted as the preferred method for reaching treatment decisions in the oncology setting including those about clinical trial participation: however, there is some disagreement between researchers over the components of SDM. Specific standardized coding systems are needed to help overcome this difficulty.


OBJECTIVE
The first objective was to describe the development of an oncology specific SDM coding system, the DAS-O. The second objective was to provide reliability and validity data supporting the DAS-O.


METHODS
Consultation data were available from tertiary cancer center out patient oncology clinics in: Australia, New Zealand (ANZ), Switzerland, Germany and Austria (SGA). Patients were women with a confirmed diagnosis of early stage breast cancer. Reliability data were from 18 randomly selected coded transcripts drawn from ANZ and SGA. Concurrent validity data are from 55 (ANZ) consultations.


METHODS
Inter and Intra rater reliability data was evaluated using Kappa correlation statistics and correlation coefficients. Correlation coefficients were used to assess concurrent validity between the DAS-O and two other SDM coding systems, OPTION and DSAT.


RESULTS
Inter and Intra rater reliability for the system were high with average Kappas of 0.58 and 0.65 respectively. Correlation coefficients between DAS-O and OPTION was 0.73 and >0.5 for DSAT.


CONCLUSIONS
We have developed a reliable and valid coding system for identifying and rating the quality of SDM in breast cancer consultations.
Brown
Richard F
RF
Department of Social and Behavioral Health, Virginia Commonwealth University School of Medicine, Richmond, VA, USA.
Butow
Phyllis N
PN
Juraskova
Ilona
I
Ribi
Karin
K
Gerber
Daniela
D
Bernhard
Jurg
J
Tattersall
Martin H N
MH
D001943:Breast Neoplasms / Q000628:therapy*; D003142:Communication; D003657:Decision Making; D005260:Female; D006801:Humans; D015588:Observer Variation; D010358:Patient Participation / Q000379:methods*; D010817:Physician-Patient Relations; D015203:Reproducibility of Results