Development and validation of the Aarhus PGD scale for operationalizing ICD-11 and DSM-5-TR TR Prolonged Grief Disorder.  

Background: Prolonged Grief Disorder (PGD) is a new disorder in ICD-11 and DSM-5-TR. There is a need for self-report tools that operationalize PGD in a valid way. The aim of this study was to develop a self-report scale to operationalize ICD-11 and DSM-5-TR PGD, the Aarhus PGD scale (A-PGDs), and assess its validity. Method: A-PGDs was developed collaboratively with clinicians and clients and tested in 349 bereaved adults (225 women). Two months post-loss the survey included demographics, depression, PTSD, anxiety, and PGD-symptoms. The A-PGDs was applied at follow-up three years post-loss. Test-retest was performed with a one-to-two-week interval. Exploratory structural equation modelling was used to test validity and factor structure. Results: Two factors, separation distress (core-symptoms) and emotional distress (associated-symptoms), emerged in the best-fitting model for both ICD-11 and DSM-5-TR. For DSM-5-TR a third factor of antagonistic feelings (bitterness, anger) was identified. Baseline PGD-symptoms predicted core-symptoms, while depression only predicted associated-symptoms. Associated-symptoms was the only factor predicting functional impairment. Test-retest reliability was generally strong (r ≤ 0.59; p <.001) on all A-PGDs items. Limitations: The use of self-report data; three years post loss; a non-clinical bereaved sample. Conclusions: Results indicate two PGD factors of core- and associated-symptoms. The relationship between associated-symptoms and functional impairment may indicate that the presence of these symptoms combined with core-symptoms constitutes disordered grief. Core-symptoms alone may be a part of normal grief. The findings indicate that the A-PGDs is a valid and reliable measure that can be used to operationalize both ICD 11 and DSM-5-TR PGD.