Background: Since the development of the Death Literacy Index (DLI) in 2019 in Australia, subsequent internationally validated versions have prompted rewording and refinement of the original survey questions. Use of the DLI in the community has also resulted in requests for a short format.
Objectives: To examine and report on the psychometric properties of a revised version of the DLI-R and develop a short format DLI-9.
Design: A cross-sectional national survey was conducted for the validation of the revised DLI.
Methods: The DLI items were revised by the research team using the international literature. DLI data were collected from a representative online non-probability panel of 1202 Australian adults, based on age, gender, and geographical location. Confirmatory factor analysis (CFA) was conducted to ensure the revised version (DLI-R) was consistent with the original. To develop a short format version of the DLI (DLI-9), items were first removed based on face validity, followed by an exploratory factor analysis (EFA) and CFA. The internal reliability of the DLI-R and the DLI-9 was assessed using Cronbach's alpha. The intraclass correlation coefficient was calculated to examine the inter-rater reliability between the DLI-R and DLI-9.
Results: Twenty-four questions in the DLI were reworded for clarity. A CFA on the 29 items of this modified version of the DLI indicated a good model fit (Tucker-Lewis Index (TLI): 0.93; Comparative Fit Index (CFI): 0.93; root mean square of approximation (RMSEA): 0.06; standardized root mean residual (SRMR): 0.06), with six latent variables and an underlying latent variable "death literacy." For the DLI-9, an EFA identified a nine-item, two-factor structure model (DLI-9). A subsequent CFA in a separate sample demonstrated a good model fit for the DLI-9 (TLI: 0.92; CFI: 0.94; RMSEA: 0.089; SRMR: 0.07). Excellent inter-rater reliability (0.98) was observed between DLI-9 and DLI-R. Cronbach's alpha coefficients for DLI-R scales and subscales and the DLI-9 all exceeded 0.8, indicating high internal consistency.
Conclusion: The DLI-R and the DLI-9 were found to have acceptable psychometric properties. The development of a shorter version of the DLI provides a valid measure of overall death literacy.
Keywords: Death Literacy Index; compassionate communities; death literacy; population studies; public health palliative care.
Progressing the Death Literacy Index: the development of a revised version (DLI-R) and a short format (DLI-9) The Death Literacy Index (DLI) is used to measure the knowledge and skills people about death and dying. Multiple countries have made their own versions, which helped improve the original questions. Community members also asked for a shorter version of the DLI. The research team updated the DLI questions using information from other studies around the world. Data was collected from 1202 Australian adults. A method called Confirmatory Factor Analysis (CFA) was used to check if the new version (DLI-R) was similar to the original. To make a shorter version, some questions were removed first, then Exploratory Factor Analysis (EFA) and CFA were used. Reliability of both versions was tested using a test called Cronbach’s alpha, and the short version was compared to the DLI-R to see if results were similar. Twenty-four questions were reworded to make them clearer. The revised 29-question version (DLI-R) worked well and showed a good fit with six main ideas under the main topic of “death literacy.” Nine questions were chosen for the shorter version (DLI-9) and were found to be closely related to the longer version. Both versions showed high reliability, meaning the questions consistently measured what they were supposed to. Both the DLI-R and the DLI-9 worked well and were found to be reliable survey tools.
© The Author(s), 2024.