Shared decision making coding systems: how do they compare in the oncology context?

The current study aimed to evaluate three coding systems which have been used to assess shared decision making in oncology consultations (OPTION, Decision Support Analysis Tool (DSAT) and Decision Analysis System for Oncology (DAS-O)): (i) comparing their ability to identify competencies of shared decision making, and (ii) determining their ability to predict patient outcomes in a single data set.

Twenty oncologists from Australia and New Zealand participated in the IBCSG Trial 33-03. The consultations of 55 women with early stage breast cancer were audio-taped, transcribed and then coded using the OPTION, DAS-O and DSAT coding systems by three different raters. Women completed the questionnaires 2 weeks and 4 months after their consultation.

DAS-O was strongly correlated with OPTION (r=0.73). DSAT was moderately correlated with DAS-O and OPTION (r<0.6). Decisional satisfaction and satisfaction with doctor SDM skills were significantly correlated with OPTION (r=0.39 and 0.42 respectively) and the latter variable was correlated with DAS-O (r=0.40). These relationships persisted in multiple linear regression analyses.

OPTION may be the most efficient and sensitive coding system for research purposes; however, DSAT appeared to document behaviours reducing decisional conflict and both DSAT and DAS-O offer more detailed feedback to doctors.

Optimal coding system will depend on research goals and training purposes.