Validity and Reliability Study of the Turkish Version of the Grief Impairment Scale

Background: The Grief Impairment Scale (GIS) was developed to assess grief-related biopsychosocial impairment and has shown robust psychometric validity across cultures. This study aimed to adapt the GIS into Turkish and examine its psychometric properties in a Turkish adult bereaved sample. Method: A cross-sectional methodological design was employed with 391 Turkish adults aged 18–65 who had lost a close relative within the past 6 months to 2 years. The adaptation process followed World Health Organizations five-step translation protocol, including forward-back translation, expert review, pilot testing, and finalization. Measures included the Sociodemographic Data Form, the Prolonged Grief Scale-Revised (PG-13-R) and the Turkish version of GIS. Results: The Turkish GIS demonstrated high internal consistency (Cronbach α = 0.854), with strong and significant item–total correlations. Factor analyses confirmed a unidimensional structure consistent with prior studies. Convergent validity was supported by significant positive correlations between GIS and PG-13-R scores, indicating that higher grief-related impairment was associated with greater severity of prolonged grief symptoms. Conclusion: Results support the Turkish GIS as a reliable and valid measure of grief-related functional impairment. The scale’s biopsychosocial model provides a multidimensional framework for assessing the broad impact of grief, extending beyond emotional symptoms to daily functioning. The Turkish GIS offers a brief, practical tool for research and clinical use in assessing grief-related functional impairment.