The ICD‐11 and DSM‐5‐TR prolonged grief criteria: Validation of the Traumatic Grief Inventory‐Self Report Plus using exploratory factor analysis and item response theory

Abstract

More recently, the prolonged grief disorder (PGD) has been recognized as a mental health disorder following bereavement, which is distinct from depression and PTSD. However, the number and proposed symptom items vary across the ICD‐11 and the DSM‐5‐TR criteria for PG. The Traumatic Grief Inventory‐Self Report Plus (TGI‐SR+), which is an updated version of the TGI‐SR, is currently the only robust instrument that assesses PG according to the ICD‐11 and DSM‐5‐TR criteria. For research and clinical use among French‐speaking countries, the forward‐backward procedure was applied to translate the TGI‐SR+ into French language. Exploratory factor analysis and parallel analysis converged towards a two‐dimensional structure for the TGI‐SR+, representing adaptation difficulties and traumatic separation distress. However, items mapping onto ICD‐11 and DSM‐5‐TR criteria for PG represented a one‐dimensional structure. Findings based on item response theory method provided strong evidence for discriminative characteristics of the items. The internal reliability was excellent for the TGI‐SR+ (McDonald's ω = 0.97) and ICD‐11 and DSM‐5‐TR criteria for PGD (McDonald's ω = 0.95). We also demonstrated a very high temporal stability for the TGI‐SR+ total score (ICC = .91, p < 0.0001) and ICD‐11 PGD and DSM‐5‐TR PGD (ICC = 0.90, and ICC = 0.88, ps < 0.0001, respectively). The concurrent validity of the instrument was also demonstrated, such that the TGI‐SR+ total score and all combinations were positively and significantly associated with the levels of depression, anxiety and post‐traumatic stress symptoms. However, the effect sizes were moderate. We conclude that for research and clinical use among French bereaved populations, the TGI‐SR+ is a sound tool with very good psychometric properties.

Psychometric evaluation of the Swedish Traumatic Grief Inventory Self‐Report Plus (TGI‐SR+) in bereaved parents

“…These study characteristics may limit the generalizability of our findings to other groups of bereaved adults. However, it should be noted that the results found in the present study were comparable to the results of past validation studies using different samples (Kokou‐Kpolou et al, 2022; Lenferink et al, 2022), which appears to suggest that the TGI‐SR+ has similar psychometric properties across different groups of bereaved adults. Nevertheless, further examinations of the Swedish TGI‐SR+ in diverse bereaved samples are warranted.…”

“…Evidence for convergent validity was provided by showing strong positive correlations between DSM-5-TR and ICD-11 PG symptom levels as assessed with the TGI-SR+ and symptoms of PTS and depression. This aligns with the well-documented strong associations of PG symptoms with symptoms of these neighbouring disorders (Kokou-Kpolou et al, 2022;Lenferink et al, 2022; for reviews see Heeke et al, 2019;Komischke-Konnerup et al, 2021). Furthermore, strong positive associations were found between DSM-5-TR and ICD-11 PG symptoms and PG symptoms per Prigerson et al (2009).…”

“…To do so, we evaluated the factor structure, reliability, convergent validity, known‐groups validity and an optimal cut‐off for probable PGD cases for items representing the DSM‐5‐TR and ICD‐11 PGD symptom sets separately. Based on prior validation studies of the Dutch and French TGI‐SR+ (Kokou‐Kpolou et al, 2022; Lenferink et al, 2022), we expected to find an acceptable fit for the unidimensional model for items representing DSM‐5‐TR and ICD‐11 PG symptoms. We did not expect a relevant improvement of fit for the two‐factor model over the one‐factor model for both criteria sets.…”

“…Prior research has examined the psychometric properties of the original Dutch TGI-SR+ (Lenferink et al, 2022) and the translated French TGI-SR+ (Kokou-Kpolou et al, 2022). Main findings are summarized here.…”

Grief and delivering a statement in court: a longitudinal mixed-method study among homicidally bereaved people

“…In case multiple losses are equally often on your mind and/or are equally stressful, please select one person while completing the questionnaire. Research demonstrated that the TGI-SR+ has good psychometric properties (Kokou-Kpolou et al, 2022 ; Lenferink, Eisma, et al, 2022 ). Cronbach’s alphas of the DSM-5-TR PGD items in this study were .93 at pre-VPS and .92 at post-VPS.…”