Diagnosis of prolonged grief disorder among older adults: mapping physicians' knowledge and practice, and evaluating the effectiveness of a brief targeted training program.

Background: Prolonged Grief Disorder (PGD) is a psychiatric diagnosis with significant implications for individuals and society. Familiarity with its diagnostic criteria and recommended interventions is essential for early detection and effective treatment. As aging naturally involves multiple losses, older adults are at distinct risk of developing PGD, a condition associated with psychological and physical comorbidities and increased mortality. In the Israeli context, this issue holds particular significance following the events of October 7, 2023, and the ensuing war, which have had - and continue to have - a profound impact on the population's mental health. Given PGD's recent inclusion in diagnostic manuals, many physicians may lack sufficient knowledge, leading to under-recognition or misdiagnosis. This gap is particularly evident among older adults, for whom the assessment and management of psychological distress are often underassessed and undertreated, highlighting the urgent need for targeted training and broader integration of existing knowledge into clinical practice. Accordingly, the present study has two main objectives: (1) to assess physicians' knowledge and use of PGD diagnostic criteria with older patients, and (2) to evaluate the effectiveness of a brief informational intervention on their understanding and diagnostic application. Methods: Using a mixed experimental design, the study will include senior physicians and residents specializing in geriatrics, psychiatry, and family medicine. Data will be collected via an online structured questionnaire containing professional background items and clinical vignettes designed to assess participants' knowledge and application of PGD diagnostic criteria. Afterwards, participants will be individually randomized (1:1) via a computer-generated sequence in a partially participant-blinded, assessor-blinded controlled trial to either an experimental group viewing an informational PGD video or a control group viewing a structurally equivalent video (matched in length, graphics, and word count) addressing bereavement in older adults without directly referencing PGD. All participants will then complete the vignettes again to evaluate the effects of the intervention. A one-month follow-up assessment will evaluate the retention of intervention effects. Discussion: This first systematic Israeli study on PGD implementation will provide an empirical basis for policy development, professional training, and prevention programs. Its findings may enhance diagnostic accuracy, improve care efficiency, reduce systemic costs, and support ongoing evaluation and refinement of clinical practices. Clinical trial registration: ClinicalTrials.gov, identifier NCT07487233.