Is it acceptable and feasible to measure prolonged grief disorder symptoms in daily life using experience sampling methodology?

Introduction: Current grief research is dominated by cross-sectional studies assessing prolonged grief disorder (PGD) symptoms retrospectively. Examining grief in daily life, using Experience Sampling Methodology (ESM), may advance the field. Because of the lack of ESM-research on PGD, we evaluated the acceptability and feasi-bility of assessing PGD symptoms in daily life of bereaved people.Materials and methods: ESM-items assessing PGD symptoms were developed using cognitive interviewing with five ESM/grief experts. Eighty bereaved adults completed these ESM-items five times a day for two weeks. Before and after this ESM-phase, interviews were administered assessing PGD retrospectively (using the Traumatic Grief Inventory-Clinical Administered). t-tests were performed comparing symptom severity of aggregated moment-to -moment recall (using ESM-items) with retrospective recall (based on interviews) of PGD symptoms. Acceptability of participating in ESM-research (assessed with the Reactions to Research Participation Questionnaire) was examined using descriptive statistics. Feasibility was evaluated by reporting compliance and retention rates.Results: Minor changes were made to the ESM-items based on expert interviews. Average levels of aggregated moment-to-moment recall of the symptoms "yearning" (d =-1.04), "preoccupation with the deceased" (d =-0.91), "marked sense of disbelief" (d =-0.43), and "intense loneliness" (d =-0.28) were lower compared with retrospective recalling these symptoms. On average, bereaved people were neutral about personal benefits gained through participation in this EMS-study. They indicated that participation did not raise emotional re-actions. Compliance and retention rates were 60% and 65%, respectively.Discussion: Our findings indicate that whereas compliance and retention is challenging, using ESM to study PGD symptoms in daily life might be useful. Nevertheless, more research is needed.