Shared Decision Making in Prostate Cancer Care-Encouraging Every Patient to be Actively Involved in Decision Making or Ensuring the Patient Preferred Level of Involvement?

Purpose: The aims of this study were to 1) describe preferred and experienced roles in treatment decision making among patients with localized prostate cancer, 2) identify how often the roles experienced by patients matched their preferred roles and 3) determine whether active involvement in decision making regardless of role preferences or concordance between preferred and experienced roles would be the strongest predictor of more favorable patient reported outcomes. Materials and Methods: In this prospective, multicenter, observational study we obtained serial questionnaire data from 454 patients with newly diagnosed, localized prostate cancer (cT1-cT2, or Gleason 7 or less and prostate specific antigen 20 ng/ml or less). Questionnaires were completed prior to treatment and at the 3, 6 and 12-month posttreatment followups. Clinical data were obtained from the patient medical records. Active involvement and role concordance were operationalized using the CPS (Control Preferences Scale). ANOVA and effect sizes (small and medium Cohen d = 0.2 and 0.5, respectively) were used to compare patient knowledge of prostate cancer, decision conflict, decision regret and overall health related quality of life. Results: Of the patients 393 (87%) reported having been actively involved in treatment decision making. However, 78 patients (17%) indicated having had less or more involvement than preferred. Active involvement was significantly associated with more prostate cancer knowledge (d = 0.30), less decision conflict (d = 0.52) and less decision regret (d = 0.34). Role concordance was also but less strongly associated with less decision conflict (d = 0.41). Conclusions: Our findings support a policy of encouraging all patients with localized prostate cancer regardless of their stated role preferences to be actively involved in the treatment decision.