Abstract
Meaningful benefit is a much-debated concept in Alzheimer's disease (AD). Research to date has primarily focused on change thresholds that are anchored in clinicians' or care partners' impressions; however, these thresholds are not inherently meaningful to people living with AD (PLWAD) and may not take their perspectives into account. By overlaying the lived experience of AD through the eyes of individual PLWAD and their care partners with clinical outcomes, we offer an important framework in which to consider meaningful benefit in terms of symptoms, functioning, and outcomes. The PLWAD and care partner interviews and surveys of the What Matters Most (WMM) research program have identified treatment-related needs, preferences, and priorities of people at risk of or living with AD and their care partners across the AD continuum. A WMM conceptual model of disease-created and refined through interviews with PLWAD and care partners across the AD severity spectrum-includes 50 concepts across six domains (social life/activities, thought processing, communication, daily activities, mood/emotion, and general independence) considered important to all PLWAD and care partners. From the PLWAD and care partner perspectives, an increase in time to the onset, development, or worsening of the symptoms in any of these meaningful concepts was considered a meaningful benefit. No single commonly used clinical outcome assessment captures all concepts of importance, nor the importance of time in AD; considering the lived experience and priorities of individuals affected by AD is crucial to put the "meaning" in "meaningful."