20170112-Robinson-Thesis.pdf (86.08 MB)
Refinement and Revalidation of the Demoralization Scale: The DS-II
thesis
posted on 2017-02-07, 01:22 authored by Sophie Anne RobinsonDemoralization is a
condition of lowered morale and maladaptive coping that involves symptoms of
hopelessness, helplessness, meaninglessness and purposelessness. When this
mental state becomes severe, it can be associated with a desire for hastened
death. The original Demoralization Scale (DS) was initially validated in 2004
as a tool to measure demoralization in advanced cancer patients. However,
subsequent studies suggested the need for psychometric improvement. The current
research aimed to address three aims and comprised two studies. Study 1
addressed the first aim which was to review the empirical research on the Demoralization
Syndrome. Study 2 was a quantitative longitudinal study that addressed the
second and third aims. The second aim was to refine and revalidate the
Demoralization Scale. The third was to explore the mediating role of
demoralization, as well as other psychological factors, in the relationship
between global quality of life and desire for hastened death.
In Study 1, the PRISMA guidelines informed a comprehensive literature review of 25 studies (4,545 participants) on the Demoralization Syndrome in patients with progressive disease, including cancer. Data on the correlation between demoralization and sociodemographic, medical, and other psychological factors were organized according to the strength of evidence. Recent empirical evidence from the past decade was synthesized to provide information on the prevalence rate of demoralization; factors related to demoralization; and the psychometric properties of demoralization measures. Prevalence rates for demoralization ranged from 13-18% in patients with progressive disease. Depressive symptoms, anxiety, single status, unemployment, and poorly controlled physical symptoms were consistently related to demoralization. The original Demoralization Scale (DS) demonstrated adequate psychometric properties across five studies, but inconsistent findings for the factor structure were reported and test-retest reliability was not examined.
In Study 2, palliative care patients (N = 211) with advanced cancer (n = 189) or other progressive diseases (neurological, cardiorespiratory and renal; n = 22) completed a battery of questionnaires, including a revised version of the original 24-item DS and measures of symptom burden (Memorial Symptom Assessment Scale), quality of life (McGill Quality of Life Scale), depression (Patient Health Questionnaire), and attitudes toward end-of-life (Schedule of Attitudes toward Hastened Death). Exploratory factor analysis and Rasch modeling were employed to evaluate, modify, and revalidate the scale. These analyzes provided information about dimensionality, appropriateness of response format, item fit, item bias, and item difficulty. Test-retest reliability was investigated for 58 symptomatically stable patients approximately five days after baseline measures were taken. Convergent validity was examined with Spearman’s rho correlations and discriminant validity was explored with Mann-Whitney U Tests, with effect sizes used to determine the minimal clinically important difference (MCID). Discriminant validity with major depression was assessed with cross-tabulation frequencies with a chi square analysis. Multiple mediation with the bootstrapping sampling procedure was undertaken to explore the mediating role of demoralization, depression, loss of perceived control, and self-worth in the relationship between global quality of life and desire for hastened death.
The results of the exploratory factor analysis supported a 22-item, 2-component model (Meaning and Purpose; and Distress and Coping Ability) of demoralization. Separate Rasch modeling of each component resulted in changing the response option categories from a 5-point to a 3-point Likert scale. Three items were removed from each subscale and the result was two 8-item subscales that met Rasch model expectations. The 16 items were appropriate to sum as a total score. The DS-II demonstrated satisfactory internal consistency (Meaning and Purpose: α = 0.84; Distress and Coping Ability: α = 0.82; Total: α = 0.89) and test-retest reliability (Meaning and Purpose: intraclass correlation [ICC] = 0.68; Distress and Coping Ability: ICC = 0.82; Total ICC = .80). Convergent validity was established for the DS-II with measures of psychological distress, quality of life, and attitudes toward end-of-life. Discriminant validity was found, as firstly, the DS-II differentiated patients with different functional performance levels and high versus low symptoms, with two points on the DS-II considered clinically meaningful. Furthermore, comorbidity with depression was not found at moderate levels of demoralization. The results of the multiple mediation analysis were that an increased level of depressive symptoms and lower levels of meaning and purpose, control, and self-worth mediated the inverse relationship between global quality of life and desire for hastened death.
Overall, the Demoralization Syndrome can be a common presentation in the palliative care setting and one which mediates the relationship between poor quality of life and the desire for hastened death. The DS-II is a psychometrically sound and appropriate measure of demoralization for patients with advanced progressive disease. Given the revalidation and simplification, the DS-II is an improved and more practical measure of demoralization for use in research and clinical settings than the original DS instrument. It will likely be a useful outcome measure for meaning-centered therapies, particularly appropriate in an era where such therapies are being trialed and in patient populations at risk of demoralization.
In Study 1, the PRISMA guidelines informed a comprehensive literature review of 25 studies (4,545 participants) on the Demoralization Syndrome in patients with progressive disease, including cancer. Data on the correlation between demoralization and sociodemographic, medical, and other psychological factors were organized according to the strength of evidence. Recent empirical evidence from the past decade was synthesized to provide information on the prevalence rate of demoralization; factors related to demoralization; and the psychometric properties of demoralization measures. Prevalence rates for demoralization ranged from 13-18% in patients with progressive disease. Depressive symptoms, anxiety, single status, unemployment, and poorly controlled physical symptoms were consistently related to demoralization. The original Demoralization Scale (DS) demonstrated adequate psychometric properties across five studies, but inconsistent findings for the factor structure were reported and test-retest reliability was not examined.
In Study 2, palliative care patients (N = 211) with advanced cancer (n = 189) or other progressive diseases (neurological, cardiorespiratory and renal; n = 22) completed a battery of questionnaires, including a revised version of the original 24-item DS and measures of symptom burden (Memorial Symptom Assessment Scale), quality of life (McGill Quality of Life Scale), depression (Patient Health Questionnaire), and attitudes toward end-of-life (Schedule of Attitudes toward Hastened Death). Exploratory factor analysis and Rasch modeling were employed to evaluate, modify, and revalidate the scale. These analyzes provided information about dimensionality, appropriateness of response format, item fit, item bias, and item difficulty. Test-retest reliability was investigated for 58 symptomatically stable patients approximately five days after baseline measures were taken. Convergent validity was examined with Spearman’s rho correlations and discriminant validity was explored with Mann-Whitney U Tests, with effect sizes used to determine the minimal clinically important difference (MCID). Discriminant validity with major depression was assessed with cross-tabulation frequencies with a chi square analysis. Multiple mediation with the bootstrapping sampling procedure was undertaken to explore the mediating role of demoralization, depression, loss of perceived control, and self-worth in the relationship between global quality of life and desire for hastened death.
The results of the exploratory factor analysis supported a 22-item, 2-component model (Meaning and Purpose; and Distress and Coping Ability) of demoralization. Separate Rasch modeling of each component resulted in changing the response option categories from a 5-point to a 3-point Likert scale. Three items were removed from each subscale and the result was two 8-item subscales that met Rasch model expectations. The 16 items were appropriate to sum as a total score. The DS-II demonstrated satisfactory internal consistency (Meaning and Purpose: α = 0.84; Distress and Coping Ability: α = 0.82; Total: α = 0.89) and test-retest reliability (Meaning and Purpose: intraclass correlation [ICC] = 0.68; Distress and Coping Ability: ICC = 0.82; Total ICC = .80). Convergent validity was established for the DS-II with measures of psychological distress, quality of life, and attitudes toward end-of-life. Discriminant validity was found, as firstly, the DS-II differentiated patients with different functional performance levels and high versus low symptoms, with two points on the DS-II considered clinically meaningful. Furthermore, comorbidity with depression was not found at moderate levels of demoralization. The results of the multiple mediation analysis were that an increased level of depressive symptoms and lower levels of meaning and purpose, control, and self-worth mediated the inverse relationship between global quality of life and desire for hastened death.
Overall, the Demoralization Syndrome can be a common presentation in the palliative care setting and one which mediates the relationship between poor quality of life and the desire for hastened death. The DS-II is a psychometrically sound and appropriate measure of demoralization for patients with advanced progressive disease. Given the revalidation and simplification, the DS-II is an improved and more practical measure of demoralization for use in research and clinical settings than the original DS instrument. It will likely be a useful outcome measure for meaning-centered therapies, particularly appropriate in an era where such therapies are being trialed and in patient populations at risk of demoralization.
