Table 1 Key Study Measures

Physical Function:

The Karnofsky Performance Status index (KPS) [53, 54]

Provides a valid and reliable rating in downward decrements of 10, from 100 (no signs/symptoms of illness) to 0 (death), of a patient’s level of physical functioning and ability to carry out activities of daily living. Administered by a member of the research staff with patient input. Modified to remove the 0 rating of “death” from the measure.

Quality of Life:

The Quality of Life at the End of Life Scale-Cancer scale (QUAL-EC) [55, 56]

A 14-item, valid and reliable self-report scale that assesses quality of life in cancer patients near the end of life with four distinct factors: symptom control, relationship with healthcare provider, preparation for end of life, and life completion. Modified: Symptom control subscale has been removed [56].

Will to Live:

Will to Live Scale (WTLS) [57]

A 5-item, self-report, validated and reliable instrument to assess the will to live.

Desire for Hastened Death:

The Schedule of Attitudes towards Hastened Death-Abbreviated (SAHD-A) [58]

A 6-item, self-report, dichotomous measure of the desire for hastened death, validated in a large sample of patients with advanced illnesses.

*Depressive Symptoms:

Patient Health Questionnaire-9

(PHQ-9) [58, 59]

A 9-item, self-report, reliable and validated measure of depressive symptoms in patients with advanced cancer. Modified: One additional question (item 9a) added to assess intent to self-harm, which is answered only if item 9 assessing suicidal ideation is endorsed positively.

Physical Symptoms:

Edmonton Symptom Assessment System-Revised (ESAS-r-cs) [60,61,62]

A revised, reliable and valid, 12-item version of the original 9-item ESAS that assesses the following common symptoms in advanced cancer and palliative care patients: pain, tiredness, drowsiness, nausea, lack of appetite, shortness of breath, depression, anxiety, and wellbeing. This recently modified version includes two additional symptoms (constipation and sleep disturbances), and the option to specify any other symptom.

*Attachment Security:

Experiences in Close Relationships-Modified (ECR-M16) [63]

A modified 16-item, self-report, validated and internally reliable measure of attachment insecurity with two 8-item subscales of attachment avoidance and attachment anxiety.

Self-Esteem:

Rosenberg Self-Esteem Scale (RSES) [64]

A widely-used, validated and reliable 10-item, self-report, measure of self-esteem.

Death Anxiety:

Death and Dying Distress Scale (DADDS) [65,66,67]

A 15-item, self-report, validated measure of death anxiety in individuals with advanced cancer.

Patient Satisfaction with Physician Communication:

Patient-Centered Communication-Cancer-6 items (PCC-Ca-6) [68]

A 6-item, valid and reliable self-report measure that assesses satisfaction with communication with doctors and other healthcare professionals such as nurses and physician assistants.

*Satisfaction with Physician Care:

Modified FAMCARE Scale P16 (FAMCARE-P16) for patients [63] and FAMCARE for caregivers [69]

Reliable and valid self-report scales capturing satisfaction with physician care for patients [63] and for caregivers [69] including items evaluating assessments of information giving, availability of care, and physical care.

Demoralization:

Demoralization Scale-II (DS-II) [70]

A 16-item, psychometrically sound self-report short-form version measuring the expression of demoralization. Contains two 8-item subscales; Meaning and Purpose, and Distress and Coping Ability.

Self-perceived Burden:

Self-perceived Burden Scale (SPBS) [71]

A reliable and valid, 9-item self-report measure of chronically ill patients’ self-perceived experience of burden on their primary caregivers. Found to have a single factor, good reliability, and good convergent and divergent validity.

*Spiritual Well-being:

Functional Assessment of Chronic Illness Therapy-Spiritual Well-Being scale (FACIT-Sp-12) for patients [72] and FACIT-Sp-NI (Non-Illness version) for caregivers [72, 73]

This widely used, reliable and valid 12-item self-report measure assesses the sense of meaning, peace, and faith in individuals with illness. Two items related to patient’s illness on the FACIT-Sp-12 were modified in the FACIT-Sp-NI (Non-Illness version of the scale) provided to caregivers (i.e., items 11 and 12 replace “illness” with “difficult times”).

*Relational Quality:

ENRICH Marital Satisfaction Scale (ENRICH) [74]

This reliable and valid 15-item, self-report scale assesses satisfaction in various areas of the marital relationship and provided both dyadic and individual satisfaction scores. Patients not currently in a long-term romantic relationship will be instructed to skip this measure. Items referring to “marriage” were modified to refer to “relationship” to ensure relevance for non-married and common-law romantic partners.

*Social Support:

The modified Medical Outcomes Study Social Support Survey (mMOS-SSS) [75, 76]

An 8-item self-report, shortened measure of social support with excellent psychometric properties [76], similar to the original 19 item scale [75]; the shortened measure provides scores for two subscales measuring emotional and instrumental (or tangible) social support.

*Religiosity:

The Duke University Religion Index (DUREL) [77]

This is a 5-item, self-report, validated and reliable measure of three dimensions of religiosity: intrinsic religiosity (subjective religiosity), organizational religious activity, and non-organization religious activity. To promote inclusiveness, “Church” was modified to “places of worship” and “Bible Study” was modified to “study of religious texts”.