A multi-centred sequential trial comparing PEGASUS, an intervention to promote shared decision making about breast...

Decision making about breast reconstruction (BR) is complex. The Patients' Expectations and Goals: Assisting Shared Understanding of Surgery (PEGASUS) intervention aims to support shared decision making by helping women and clinicians clarify and discuss their expectations around reconstructive surgery. We conducted a multi-centred sequential trial comparing PEGASUS (n = 52) with usual care (UC) (n = 86) in women considering reconstruction, who completed outcome measures at baseline, and 3, 6 and 12 months post-surgery. The primary outcome was BR-specific quality of life (Breast-Q) 6 months post-intervention. Secondary outcomes were health-related quality of life (EQ-5D-5L), capabilities (ICECAP-A) and decisional regret, compared using t-tests and Cohen's d. Comparative analyses revealed no significant differences between groups in Breast-Q scores at any time point, except for a favourable effect for UC on psychological well-being at 3 months (t = -2.41, p = .019, d= -0.59). Intervention participants reported significantly higher, therefore improved, ICECAP-A (t = -2.13, p = .037, d = -0.45) and EQ VAS (t = -2.28, p = .026, d = -0.49) scores at 12 months compared to UC. Decisional regret was significantly lower in the PEGASUS group compared to the UC group at 6 months (t =2.06, p = .044, d= -0.51), but this was not sustained at 12 months. In conclusion, the PEGASUS intervention offers some benefits to women considering BR. At times, women experienced less decisional regret, improved health-related quality of life and capability well-being. Findings are discussed in the light of fidelity testing and embedding PEGASUS into practice.