Validation of a culturally adapted Swedish-language version of the Death Literacy Index

Therese Johansson; Åsa Olsson; Carol Tishelman; Kerrie Noonan; Rosemary Leonard; Lars E Eriksson; Ida Goliath; Joachim Cohen

doi:10.1371/journal.pone.0295141

Validation of a culturally adapted Swedish-language version of the Death Literacy Index

PLoS One. 2023 Nov 30;18(11):e0295141. doi: 10.1371/journal.pone.0295141. eCollection 2023.

Authors

Therese Johansson^{1

2}, Åsa Olsson^{1

3}, Carol Tishelman^{4

5

6}, Kerrie Noonan^{7

8

9}, Rosemary Leonard⁷, Lars E Eriksson^{1

10

11}, Ida Goliath^{1

12}, Joachim Cohen⁶

Affiliations

¹ Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden.
² Cicely Saunders Institute of Palliative Care, Policy & Rehabilitation, King's College London, London, United Kingdom.
³ Swedish National Graduate School on Ageing and Health (SWEAH), Lund University, Lund, Sweden.
⁴ Department of Learning, Informatics, Management and Ethics, Karolinska Institutet, Solna, Sweden.
⁵ Stockholm Health Care Services, Region Stockholm, Sweden.
⁶ End-of-Life Care Research Group, Vrije Universiteit Brussel and Ghent University, Brussels, Belgium.
⁷ School of Social Sciences, Western Sydney University, Sydney, Australia.
⁸ Death Literacy Institute, Australia.
⁹ Public Health Palliative Care Unit, La Trobe University, Melbourne, Australia.
¹⁰ School of Health and Psychological Sciences, City, University of London, London, United Kingdom.
¹¹ Medical Unit Infectious Diseases, Karolinska University Hospital, Huddinge, Sweden.
¹² Stockholm Gerontology Research Center, Stockholm, Sweden.

Abstract

The death literacy index (DLI) was developed in Australia to measure death literacy, a set of experience-based knowledge needed to understand and act on end-of-life (EOL) care options but has not yet been validated outside its original context. The aim of this study was to develop a culturally adapted Swedish-language version of the DLI, the DLI-S, and assess sources of evidence for its validity in a Swedish context. The study involved a multi-step process of translation and cultural adaptation and two validation phases: examining first content and response process validity through expert review (n = 10) and cognitive interviews (n = 10); and second, internal structure validity of DLI-S data collected from an online cross-sectional survey (n = 503). The psychometric evaluation involved analysis of descriptive statistics on item and scale-level, internal consistency and test-retest reliability, and confirmatory factor analysis. During translation and adaptation, changes were made to adjust items to the Swedish context. Additional adjustments were made following findings from the expert review and cognitive interviews. The content validity index exceeded recommended thresholds (S-CVIAve = 0.926). The psychometric evaluation provided support for DLI-S' validity. The hypothesized six-factor model showed good fit (χ2 = 1107.631 p<0.001, CFI = 0.993, TLI = 0.993, RMSEA = 0.064, SRMR = 0.054). High internal consistency reliability was demonstrated for the overall scale (Cronbach's α = 0.94) and each sub-scale (α 0.81-0.92). Test-retest reliability was acceptable, ICC ranging between 0.66-0.85. Through a comprehensive assessment of several sources of evidence, we show that the DLI-S demonstrates satisfactory validity and acceptability to measure death literacy in the Swedish context. There are, however, indications that the sub-scales measuring community capacity perform worse in comparison to other sca and may function differently in Sweden than in the original context. The DLI-S has potential to contribute to research on community-based EOL interventions.

Copyright: © 2023 Johansson et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

MeSH terms

Cross-Sectional Studies
Language*
Literacy*
Psychometrics
Reproducibility of Results
Surveys and Questionnaires
Sweden

Grants and funding

“This study was funded by Strategic Research Area Health Care Science (SFO‐V), Karolinska Institutet; the Doctoral School in Health Care Sciences, Karolinska Institutet; Forskningsrådet om Hälsa, Arbetsliv och Välfärd (Swedish Research Council for Health, Welfare and Working Life, grant number 2014-04071); Stockholm City Elder Care Bureau; and Stockholm Gerontology Research Center. The funders had no part in, nor influence on, the study design, data collection, analysis, interpretation, or writing of results.”.