Evaluation of a Shared Decision Making Program for women suspected to have a genetic predisposition to breast cancer: preliminary results

Women with a suspected genetic predisposition for breast cancer face the difficult choice between participation in a breast cancer screening program and prophylactic mastectomy. We developed a Shared Decision Making Program (SDMP) to support this decision. Objectives. To evaluate the SDMP on practicality, beneficial effects, and satisfaction. Design. A one-group pretest-posttest design was used. Measures. The measures comprised decision uncertainty, decision burden, subjective knowledge and risk comprehension: these were assessed before and after the SDMP. Additional measures were obtained for concepts related to breast cancer concern, wish to participate, satisfaction, acceptability, and emotional reaction to information material. Results. Seventy-two women, most of whom were awaiting the genetic test results, participated. Decision uncertainty (effect size d = 0.37) and decision burden (d = 0.41) improved. Subjective knowledge (averaged d = 0.94) and risk comprehension also improved. Women were satisfied with the SDMP and found its rationale acceptable. Women with a strong emotional reaction to the information material benefited less, whereas women with a stronger wish to participate in the decision benefited more from the SDMP. Conclusions. There is a need for more information, especially on prophylactic mastectomy and among gene carriers. Beneficial effects were observed both for women with unknown and known genetic status. This suggests that information concerning treatment options should be made available as soon as DNA testing begins. Better psychological outcomes for women with a stronger wish to participate may arise because wish to participate items are characteristic of an emotionally stable personality. Key words: shared decision making; breast cancer; genetic predisposition; patient participation; patient satisfaction