Background: Huntington disease is a fatal inherited neurodegenerative disease. Because the end result of Huntington disease is death due to Huntington disease-related causes, there is a need for better understanding and caring for individuals at their end of life.
Aim: The purpose of this study was to develop a new measure to evaluate end of life planning.
Design: We conducted qualitative focus groups, solicited expert input, and completed a literature review to develop a 16-item measure to evaluate important aspects of end of life planning for Huntington disease. Item response theory and differential item functioning analyses were utilized to examine the psychometric properties of items; exploratory factor analysis was used to establish meaningful subscales.
Participants: Participants included 508 individuals with pre-manifest or manifest Huntington disease.
Results: Item response theory supported the retention of all 16 items on the huntington disease quality of life ("HDQLIFE") end of life planning measure. Exploratory factor analysis supported a four-factor structure: legal planning, financial planning, preferences for hospice care, and preferences for conditions (locations, surroundings, etc.) at the time of death. Although a handful of items exhibited some evidence of differential item functioning, these items were retained due to their relevant clinical content. The final 16-item scale includes an overall total score and four subscale scores that reflect the different end of life planning constructs.
Conclusions: The 16-item HDQLIFE end of life planning measure demonstrates adequate psychometric properties; it may be a useful tool for clinicians to clarify patients' preferences about end of life care.
Keywords: End of life; HDQLIFE; HDQLIFE Site Investigators and Coordinators; Health-related quality of life; Huntington disease; Patient-reported outcome (PRO).