Prolonged Grief Disorder, depression, and posttraumatic stress disorder are distinguishable syndromes.

Background: This study examined the distinctiveness of symptoms of Prolonged Grief Disorder (PGD), depression, and posttraumatic stress disorder (PTSD). We compared the fit of a one-factor model with the fit of four hierarchical models in which symptoms formed three distinct correlated higher-order dimensions, and PTSD-items were modeled in different ways.
Methods: Self-reported data were available from two samples; 572 mourners recruited via the internet and 408 mourners recruited via healthcare workers.
Results: In Sample 1, the unitary model did not fit the data. The four hierarchical models all fit better. The model in which PTSD-items constituted four lower-order factors of reexperiencing, avoidance, dysphoria, and hyperarousal fit the data best. The fit was further improved, when one weak PGD-item and one weak PTSD-item were removed, and error-terms of similar items were allowed to correlate. Findings from Sample 1 were replicated in Sample 2.
Limitations: This study relied on self-reported data. Not all PGD-criteria and depression-criteria were assessed.
Conclusions: This is the first confirmatory factor analysis study showing that symptoms of PGD, depression, and PTSD represent distinguishable syndromes. PGD-symptoms should be addressed in the assessment and treatment of bereaved people seeking treatment.
(2010 Elsevier B.V. All rights reserved.)