مسلم رجبی

Background: Grief is a natural and universal response to the loss of a loved one. The grief experience is not a state but a process. Most individuals recover adequately within a year after the loss; however, when individuals experience an extension of the standard grieving process, they are said to be experiencing prolonged grief disorder, thought to result from failure to transition from acute to integrated grief. Therefore, validating tools related to grief in different cultures can provide the ground for measuring its concept by the culture to understand the cultural differences of this structure. Aims: This study aimed to investigate the psychometric properties, reliability, and validity of PG-13-R. Methods: Data were collected from two independent samples of 285 (exploratory factor analysis) and 241 (confirmatory factor analysis) mourning adults to determine whether the findings explored in one sample can be verified in another. Face and content validity were measured quantitatively and qualitatively. Concurrent validity was measured using correlation coefficient calculation with the Posttraumatic Stress Disorder Checklist (PCL-5), the Generalized Anxiety Disorder scale (GAD-7), and the Beck Depression Inventory-II (BDI-II). The collected data were analyzed using SPSS.27 and AMOS.26 software. Exploratory factor analysis was performed using principal components and the Varimax method. Confirmatory factor analysis was performed using AMOS.26 software. Results: The exploratory and confirmatory factor analyses supported the two-factor structure with emergent distress, detachment, and meaninglessness factors. These factors had acceptable internal consistency. PG-13-R factors had good convergence validity with depression, anxiety, post-traumatic stress disorder, and bereavement experience (P< 0.05). Cronbach's alpha coefficient (α) was 0.78 for Distress and 0.79 for Detachment and Meaning factor, and 0.87 for the whole scale, indicating good internal consistency Conclusion: PG-13-R is a useful and reliable tool for measuring PGD symptoms in the Iranian population. It is suggested that future studies examine this scale in people who have been bereaved for various reasons, including (death by suicide, sudden death, and death by accident).