From Snapshots to Dynamics: How Ecological Momentary Assessment Captures Loneliness in Later Life

Loneliness in later life is a dynamic, context-dependent experience that may fluctuate across time and everyday situations. Conventional retrospective questionnaires primarily capture average loneliness over a specified period and may overlook short-term within-person variation. Ecological momentary assessment (EMA) and related intensive longitudinal methods enable repeated assessment in daily life, offering greater temporal and ecological resolution. However, existing EMA evidence on loneliness among older adults remains fragmented, and approaches to measurement, sampling, and analysis vary substantially. This scoping review aims to systematically map how EMA and related intensive longitudinal methods have been used to assess loneliness in later life. It will summarize study and participant characteristics; EMA protocol features, including assessment frequency, duration, devices, prompting schedules, and adherence; the operationalization and psychometric properties of momentary loneliness; statistical approaches and analytical timescales; and the social, emotional, behavioral, environmental, cognitive, and health-related factors associated with loneliness in daily life. Only studies that directly and repeatedly assess loneliness during EMA, experience-sampling, or intensive diary occasions will be included. The review will provide a structured overview of current evidence on the measurement, within-person variability, contextual correlates, and temporal associations of loneliness in later life. Expected outcomes include identifying methodological inconsistencies, under-researched populations and settings, and priorities for future research. The findings are intended to inform the design and reporting of more temporally precise and context-sensitive studies and interventions addressing loneliness among older adults.