An Individualized, Interactive, and Advance Care Planning Intervention Promotes Transitions in Prognostic Awareness States Among Terminally Ill Cancer Patients in Their Last Six Months—A Secondary Analysis of a Randomized Controlled Trial

Context/Objectives: To examine whether an advance care planning intervention randomized controlled trial facilitates terminally ill cancer patients' transitions to accurate prognostic awareness (PA) and the time spent in the accurate PA state in patients' last six months. Methods: Participants (N = 460) were randomized 1:1 to experimental (interactive intervention tailored to participants' readiness for advance care planning/prognostic information) and control (symptom management education) arms with similar formats. PA was categorized into four states: 1) unknown and not wanting to know; 2) unknown but wanting to know; 3) inaccurate awareness; and 4) accurate awareness. Intervention effectiveness in the two outcomes was evaluated by intention-to-treat analysis with multistate Markov modeling (effect size ≥0.2 as minimal clinically important difference). Results: The final sample constituted 188 and 184 experimental arm and control arm participants who died and were repeatedly assessed, respectively. Experimental arm participants in States 1–3 had a higher probability of shifting to accurate PA (23.0%–35.4% vs. 15.2%–26.2%) than control arm participants, and all effect sizes met the minimal clinically important difference criterion (effect sizes 0.22–0.49). In their last six months, experimental arm participants spent more time in States 3 and 4 (0.18 vs. 0.08 and 2.94 vs. 2.38 months, respectively) but less time in States 1 and 2 (2.70 vs. 3.19 and 0.18 vs. 0.36 months, respectively) (effect sizes 0.11–0.19). Conclusion: Our intervention meaningfully facilitated participants' transition toward accurate PA and more time spent in the accurate PA state (State 4). Our intervention can help health care professionals foster cancer patients' accurate PA earlier in the terminal illness trajectory to make informed end-of-life care decisions tailored to their readiness for prognostic information.