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Psychometric properties of the PG-13-R scale to assess prolonged grief disorder among bereaved Iranian adults

Published online by Cambridge University Press:  13 April 2023

Ahmad Ashouri Open the ORCID record for Ahmad Ashouri [Opens in a new window] ,
Shahab Yousefi Open the ORCID record for Shahab Yousefi [Opens in a new window]  and
Holly G. Prigerson Open the ORCID record for Holly G. Prigerson [Opens in a new window]
Ahmad Ashouri
Affiliation:
Department of Clinical Psychology, School of Behavioral Sciences and Mental Health (Tehran Institute of Psychiatry), Iran University of Medical Sciences, Tehran, Iran
Shahab Yousefi*
Affiliation:
Department of Clinical Psychology, School of Behavioral Sciences and Mental Health (Tehran Institute of Psychiatry), Iran University of Medical Sciences, Tehran, Iran
Holly G. Prigerson
Affiliation:
Cornell Center for Research on End-of-Live Care, Weill Cornell Medicine, New York, NY, USA Department of Medicine, Division of Geriatrics and Palliative Medicine, Weill Cornell Medicine, New York, NY, USA
*
Author for correspondence: Shahab Yousefi, Department of Clinical Psychology, School of Behavioral Sciences and Mental Health (Tehran Institute of Psychiatry), Mansouri St., Niayesh St., Sattarkhan Blvd, Tehran, Iran. Email: shahabyousefin@gmail.com
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Abstract

Objectives

The PG‐13‐Revised (PG-13-R) is a self-report measure to assess prolonged grief disorder (PGD) in terms of Diagnostic and Statistical Manual of Mental Disorders, fifth revision, Text Revision. This measure has been shown to yield good psychometric properties in Western samples. This study aimed to evaluate the psychometric properties of the Persian PG-13-R.

Methods

Three hundred forty-seven individuals (209 women and 138 men) fully completed the scales. The participants were recruited using convenience sampling. The confirmatory factor analysis (CFA), convergent and divergent validity, and reliability of the Persian version of the PG-13-R were evaluated.

Results

CFA results of a unidimensional model support the construct validity of this version of the PG-13-R. The results of this study demonstrated that this version of the PG-13-R has internal consistency reliability (omega coefficient of 0.93), and the test–retest reliability with an interval of 6 weeks was 0.89. The convergent and divergent validity was shown with significant correlations between the PG-13-R and measures of depression, PTSD, functional impairment, and hope.

Significance of results

Overall, the Persian version of the PG-13-R showed good psychometric properties in the Iranian population.

Keywords

Prolonged grief disorderDSM-5-TRPG-13-Rbereavementreliability
Type
Original Article
Information
Palliative & Supportive Care , Volume 22 , Issue 1 , February 2024 , pp. 174 - 181
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Copyright
© The Author(s), 2023. Published by Cambridge University Press.

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