McGill Quality of Life Questionnaire (MQOL)

Abstract

The McGill Quality of Life Questionnaire (MQOL) is a multidimensional, patient-reported outcome measure specifically formulated, refined, and validated to assess the subjective quality of life (QOL) of individuals living with life-threatening, progressive, and advanced medical illnesses, particularly within palliative care and end-stage oncology settings. Developed by S. Robin Cohen, Balfour M. Mount, and colleagues at McGill University in Montreal, Canada, the instrument was conceived to overcome critical psychometric and conceptual limitations present in traditional health-related quality of life (HRQOL) instruments, such as the Medical Outcomes Study 36-Item Short-Form Health Survey (SF-36) or the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30). Traditional tools heavily conflate quality of life with functional performance status and physical symptom burden—parameters that inevitably deteriorate in terminal trajectory.

The MQOL operationalizes quality of life across five primary subscales: Physical Symptoms (incorporating patient-nominated physical issues), Physical Well-Being, Psychological Well-Being, Existential Well-Being, and Support, alongside a standalone single-item measure of Overall Quality of Life (Part A) and an optional qualitative exploration of subjective determinants (Part D). Comprising 16 core quantitative items (plus the introductory global item), the MQOL utilizes 11-point numerical rating scales (anchored from 0 to 10 or 1 to 10) customized with semantic differential poles designed to minimize response bias. The questionnaire specifically queries the previous two-day timeframe, balancing clinical responsiveness to rapidly fluctuating palliative trajectories with temporal stability.

Extensive psychometric investigations have affirmed the robust properties of the MQOL. Internal consistency reliability across international cohorts demonstrates high homogeneity, with Cronbach’s alpha values typically ranging between 0.83 and 0.88 for the total instrument and between 0.70 and 0.88 across individual subscales. Construct, convergent, and discriminant validities have been corroborated via structural equation modeling, exploratory and confirmatory factor analyses, and significant correlations with validated legacy scales such as the Spitzer Quality of Life Index and the Schedule for the Evaluation of Individual Quality of Life (SEIQoL). Uniquely, empirical data collected via the MQOL confirm that existential integrity and perceived support remain potent predictors of global well-being even when physical decline is absolute, establishing the instrument as a foundational paradigm shift in clinical end-of-life psychometrics.

Keywords

McGill Quality of Life Questionnaire, MQOL, palliative care, oncology, existential well-being, psychometrics, health-related quality of life, patient-reported outcome measures, terminal illness, symptom burden, spiritual well-being, end-of-life care

Authors

The McGill Quality of Life Questionnaire was conceptualized, designed, and psychometrically standardized through the collaborative leadership of pioneering researchers at the Palliative Care Service and Division of Palliative Care at McGill University, Montreal, Quebec, Canada:

• S. Robin Cohen, PhD: Professor, Departments of Oncology and Medicine, McGill University; Senior Investigator, Lady Davis Institute for Medical Research, Jewish General Hospital, Montreal, Canada. Dr. Cohen is an internationally renowned psychometrician and palliative care researcher specializing in quality-of-life measurement across terminal illness trajectories and family caregiving dynamics.
• Balfour M. Mount, OC, OQ, MD, FRCSC: Emeritus Professor of Medicine, McGill University; surgical oncologist recognized globally as the “father of Canadian palliative care,” having coined the term “palliative care” and founded the first comprehensive university-affiliated palliative care service at the Royal Victoria Hospital in 1974.
• Marita I. Strobel, MSc: Research Associate and biostatistician, McGill University Palliative Care Research Team, Montreal, Canada.
• Francoise Bui, MD: Clinical palliative care fellow and collaborating clinician, Royal Victoria Hospital, McGill University Health Centre.
• Eduardo Bruera, MD: Professor and Chair, Department of Palliative, Rehabilitation, and Integrative Medicine, The University of Texas MD Anderson Cancer Center (collaborator in the Canadian multicenter validation studies; formerly at the Cross Cancer Institute and University of Alberta).
• Marcel Provost, PhD, Jocelyne Rowe, RN, MSc, and K. Tong, MD: Collaborating investigators across Canadian palliative networks participating in the initial multicenter structural validation trials.

Purpose

The primary clinical and psychometric purpose of the McGill Quality of Life Questionnaire is to provide an accurate, clinically feasible, and theoretically grounded assessment of subjective well-being in patients diagnosed with far-advanced, life-threatening, or terminal disease. Prior to the mid-1990s, standard oncology clinical trials and epidemiological health surveys utilized measurement paradigms overwhelmingly dominated by the assessment of physical functioning, activities of daily living (ADLs), Karnofsky Performance Scale (KPS) scores, and biomedical symptom checklists. In patients receiving curative or adjuvant therapies, functional ability often directly mirrors general health status. However, in advanced malignancies, end-stage organ failure, or progressive neurodegenerative disorders, functional decline is an inevitable biological reality.

When applied to palliative populations, conventional instruments consistently produce a “floor effect”—falsely indicating that quality of life is universally catastrophic because the patient can no longer ambulate, work, or attend to personal hygiene independently. Clinicians and researchers observed a profound clinical paradox: many individuals near the end of life, despite profound physical frailty, report moments of profound serenity, personal transcendence, relational reconciliation, and high subjective life quality. The MQOL was expressly engineered to capture this paradox, demonstrating that functional impairment does not necessarily preclude an acceptable, or even rich, quality of life.

In clinical practice, the MQOL serves as an individualized assessment tool that flags domains of acute distress. The open-ended architecture of Part B (in which respondents identify up to three of their own most troublesome physical symptoms rather than rating a rigid 30-item checklist) enables clinicians to prioritize symptom management based on what matters most to the individual patient. This patient-centered approach prevents survey fatigue in frail individuals. Furthermore, the questionnaire systematically screens for psychological morbidity (e.g., anxiety, depression, hopelessness) and existential despair, alerting the interdisciplinary team—physicians, nurses, social workers, spiritual care counselors, and psychologists—to target interventions effectively.

In research contexts, the MQOL functions as a robust primary or secondary endpoint in clinical trials testing palliative interventions, hospice models of care, psychosocial therapies, pharmacotherapies for refractory symptoms, and spiritual support modalities. Because of its responsiveness over brief intervals (anchored specifically to the “past 2 days”), it reliably tracks within-person trajectories over time, facilitating longitudinal evaluation of disease burden versus therapeutic efficacy without placing an onerous burden on fatigued participants.

Psychological Construct

The core construct measured by the MQOL is Subjective Quality of Life in Advanced Illness. Under the McGill operational model, quality of life is conceptualized as an intrinsically subjective, dynamic, and multidimensional appraisal encompassing physical, emotional, relational, and philosophical facets of personal existence. It is determined not merely by the objective presence of illness or physical deficits, but by the degree of congruence between a person’s current reality and their expectations, goals, and capacity to derive meaning from their immediate experience.

The instrument deconstructs this global construct into several correlated yet distinct dimensions:

1. Global / Overall Quality of Life (Part A)

This single-item construct reflects the holistic evaluation of one’s life across all facets (physical, emotional, social, spiritual, and financial) simultaneously. Psychometrically, global single items serve as external criteria to validate subscale weighting and capture the patient’s spontaneous integration of disparate life domains into an overarching evaluation of their well-being.

2. Physical Symptoms (Part B: Items 1–3)

Rather than presuming a standardized hierarchy of physical complaints, this domain captures the idiosyncratic, personally salient symptom burden experienced by the patient over the preceding 48 hours. By inviting the individual to nominate up to three troublesome symptoms (e.g., dyspnea, nausea, intractable pain, severe fatigue, constipation) and rate the perceived disruption on an 11-point severity continuum, the construct measures *perceived problem magnitude* rather than objective biological pathology.

3. Physical Well-Being (Part B: Item 4)

Represented by an overarching somatic evaluation of feeling “physically terrible” versus “physically well,” this domain captures the broad visceral, somatic tone of bodily vitality or decay, distinguishing localized symptom complaints from a generalized systemic sense of biological distress.

4. Psychological Well-Being (Part C: Items 5–8)

This subscale assesses the affective disruptions common to severe illness, focusing on four primary psychological states: depressive symptomatology (Item 5), nervousness/worry/anxiety (Item 6), pervasive sadness (Item 7), and existential dread or terror concerning the future (Item 8). The construct captures the intensity of emotional distress and reactive mood deregulation evoked by life-limiting diagnoses.

5. Existential Well-Being (Part C: Items 9–14)

Arguably the most distinctive and theoretically innovative dimension of the MQOL, existential well-being reflects the extent to which an individual experiences purpose, dignity, personal integrity, and agency amidst dying. It evaluates six distinct facets:

• Meaning and Purpose (Item 9): The perception that life remains purposeful versus entirely devoid of significance.
• Goal Fulfillment (Item 10): Retrospective appraisal of life achievement and progress toward personal life fulfillment.
• Life Value / Worthwhileness (Item 11): The cognitive conviction that one’s cumulative life history has possessed genuine value versus being completely worthless.
• Personal Autonomy / Internal Locus of Control (Item 12): The subjective sense of holding control over one’s choices and circumstances versus feeling entirely powerless.
• Self-Esteem / Self-Regard (Item 13): The maintenance of positive self-worth and unconditional self-acceptance despite bodily deterioration.
• Temporal Appraisal / Perspective on Time (Item 14): Experiencing recent days as a “gift” versus an intolerable “burden.”

6. Support Domain (Part C: Items 15–16)

This social-relational construct assesses interpersonal connectedness and environmental responsiveness. Item 15 examines the patient’s perception of the broader social environment—whether the world is experienced as cold, hostile, and impersonal, or caring and responsive to vulnerability. Item 16 evaluates perceived emotional and social support, measuring the subjective confidence that one is held, valued, and sustained by significant others, caregivers, and community.

Theoretical Framework

The conceptual architecture of the McGill Quality of Life Questionnaire is grounded in the humanistic, existential, and biopsychosocial paradigms of medicine, drawing substantially upon the work of Viktor Frankl, Eric Cassell, and Balfour Mount’s clinical philosophy of whole-person care.

Cassell’s Nature of Suffering and the Person-Body Dichotomy

A central pillar of the MQOL’s theoretical foundation is Eric Cassell’s landmark treatise on The Nature of Suffering and the Goals of Medicine (1982, 1991). Cassell established that suffering occurs not in bodies, but in *persons*. Suffering is provoked when an impending destruction of the person is perceived, continuing until the threat has passed or the integrity of the person can be reconstituted. Crucially, pain and suffering are distinct: severe bodily pain may be borne without suffering if it carries a redemptive or benign meaning (such as childbirth), whereas mild pain accompanied by the existential conviction that one’s body is failing can induce catastrophic suffering.

Consequently, Cohen and Mount operationalized the MQOL to measure person-centered integrity rather than body-centered pathology. By disentangling somatic deterioration from the internal existential and relational domains, the MQOL posits that a patient may suffer severe biological disruption while simultaneously maintaining, or even strengthening, their psychological and existential integrity.

Frankl’s Logotherapy and the Will to Meaning

The existential subscale of the MQOL is directly rooted in Viktor Frankl’s logotherapy (1959). Frankl proposed that the primary human motivational force is the “will to meaning.” According to Frankl, meaning can be discovered through creative values (work, deeds), experiential values (encountering nature, art, love), and, most fundamentally, attitudinal values—the stance one chooses to take when confronted with an unchangeable, tragic fate (the “tragic triad” of pain, guilt, and death).

In the final stages of life, creative and experiential possibilities narrow drastically. Therefore, quality of life hinges upon attitudinal values: finding that one’s life had value, that suffering is not entirely meaningless, and that one’s remaining time can be received as a gift. The MQOL operationalizes these attitudinal constructs, enabling the measurement of meaning-making processes that serve as psychological buffers against terminal despair.

Mount’s Paradigm of Healing versus Curing

Balfour Mount articulated the paradox that while *curing* denotes the biomedical eradication of disease (an impossible goal in terminal illness), *healing* remains achievable until the final breath. Healing is defined as the journey toward personal wholeness, psychological integration, and relational reconciliation. The MQOL was constructed specifically to serve as a compass for this healing process, demonstrating empirically that quality of life can ascend in the final weeks of life if existential distress is mitigated and relational support is fortified, despite an objectively falling trajectory of functional independence.

Validity

The psychometric validity of the McGill Quality of Life Questionnaire has been confirmed across diverse clinical trials, cross-sectional cohort studies, and longitudinal investigations internationally.

Content and Face Validity

The initial generation of MQOL items was derived through rigorous qualitative research, extensive clinical interviews with palliative care patients, family caregivers, and multidisciplinary healthcare professionals across Canada. Cognitive debriefing sessions established that patients found the items deeply meaningful, non-intrusive, and reflective of their daily struggles. Unlike instruments imposing an exhaustive inventory of irrelevant physical symptoms, patients appreciated the capacity to nominate their own primary complaints in Part B, which preserved high face validity and prevented cognitive fatigue.

Construct and Structural Validity

Construct validity has been extensively demonstrated across several landmark studies. In the initial validation study conducted by Cohen, Mount, Strobel, and Bui (1995) among patients with advanced cancer and terminal non-malignant diagnoses ($N = 145$), correlations between the individual subscales and the single-item Part A (Overall Quality of Life) supported the multidimensional construct. Subsequent multicenter investigations (Cohen et al., 1997; $N = 241$) verified that the Existential subscale accounted for the greatest proportion of variance in overall quality of life, outperforming both the Physical Symptoms subscale and physical functional scores.

Convergent and Discriminant Validity

Convergent validity was verified by comparing the MQOL against established legacy instruments:

• Spitzer Quality of Life Index (QL-Index): Correlations between the MQOL Total Score and the Spitzer QL-Index were strong and statistically significant ($r = 0.55$ to $r = 0.72$, $p < 0.001$).
• EORTC QLQ-C30: The MQOL Physical Symptoms and Physical Well-Being subscales correlated robustly with the EORTC Physical Functioning and Symptom scales ($r > 0.60$), while the MQOL Psychological subscale demonstrated high convergence with the EORTC Emotional Functioning scale ($r = 0.68$).
• Discriminant Validity: Importantly, the Existential Well-Being and Support subscales displayed low to moderate correlations ($r < 0.30$) with the Karnofsky Performance Scale (KPS) and Eastern Cooperative Oncology Group (ECOG) performance status. This empirical divergence confirmed that the existential and interpersonal domains measure dimensions of human experience distinct from purely physiological functional capacity.

Known-Groups Validity and Clinical Responsiveness

The MQOL reliably discriminates between clinical subgroups. Patients categorized by palliative clinicians as experiencing acute existential crises, major depressive episodes, or unmanaged pain crises scored significantly lower on their respective MQOL subscales ($p < 0.001$). Furthermore, longitudinal validation studies demonstrate that the MQOL is sensitive to therapeutic change; palliative interventions (such as nerve blocks for intractable pain, meaning-centered psychotherapy, or pastoral counseling) produced statistically significant improvements in domain scores over 48- to 72-hour assessment windows.

Reliability

The reliability of the McGill Quality of Life Questionnaire has been confirmed across varied cultural, linguistic, and disease-specific cohorts.

Internal Consistency Reliability

Across the published psychometric literature, the MQOL demonstrates strong internal consistency reliability as evaluated by Cronbach’s alpha. In the primary Canadian multicenter validation trial (Cohen et al., 1997), the coefficients observed across domains were as follows:

• Total MQOL Scale: $\alpha = 0.88$ (indicating excellent overall instrument cohesion without redundant item duplication).
• Existential Well-Being Subscale: $\alpha = 0.83$ to $0.86$ (demonstrating that the six existential items cohere into a unified construct).
• Psychological Well-Being Subscale: $\alpha = 0.82$ to $0.85$.
• Physical Well-Being / Physical Symptoms: $\alpha = 0.72$ to $0.78$ (noting that patient-nominated physical complaints naturally exhibit higher clinical heterogeneity).
• Support Subscale: $\alpha = 0.70$ to $0.76$ (acceptable for a two-item dyad).

Subsequent international validation studies—including Italian, Spanish, Mandarin, Japanese, and Korean adaptations—have routinely replicated total Cronbach’s alpha coefficients exceeding $0.85$, confirming robust cross-cultural stability.

Test-Retest Reliability and Stability

Evaluating test-retest reliability in advanced palliative cohorts presents unique psychometric challenges, as a patient’s physiological and symptomatic state fluctuates rapidly. Nevertheless, studies examining clinically stable palliative cohorts reassessed over a 24- to 48-hour window demonstrate intra-class correlation coefficients (ICC) ranging between $0.74$ and $0.89$ for the total score and individual subscales, establishing acceptable temporal stability during steady clinical phases.

Factor Analysis

The underlying factor structure of the McGill Quality of Life Questionnaire has been scrutinized through both exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) across numerous terminal cancer and non-cancer samples.

Exploratory Factor Analysis (EFA)

In the foundational validation studies by Cohen and colleagues (1995, 1997), principal components analysis with varimax and oblimin rotations consistently identified a stable four- or five-factor structure accounting for over 65% of the total variance across Part B and Part C items:

• Factor 1: Existential Well-Being: Items 9, 10, 11, 12, 13, and 14 cleanly loaded onto this primary factor with high factor loadings ($0.58$ to $0.84$). Notably, Item 14 (“A burden” vs. “A gift”) and Item 11 (“Completely worthless” vs. “Very worthwhile”) consistently demonstrate the highest loadings on this dimension.
• Factor 2: Psychological Well-Being: Items 5, 6, 7, and 8 clustered distinctly with loadings ranging from $0.62$ to $0.83$, confirming that depressive affect, nervousness, sadness, and fear of the future form an emotional distress latent variable.
• Factor 3: Physical Well-Being / Symptoms: Item 4 (“Physically terrible” vs. “Physically well”) and the severity ratings of patient-nominated symptoms from Part B clustered onto a somatic factor (loadings $0.60$ to $0.79$).
• Factor 4: Support: Items 15 and 16 clustered to form the social/relational factor, with loadings of $0.69$ (Item 15) and $0.82$ (Item 16).

Confirmatory Factor Analysis (CFA) and Structural Equation Modeling

Subsequent psychometric evaluations utilizing structural equation modeling to test the hypothesized multi-factor models have confirmed acceptable goodness-of-fit indices. In confirmatory models, the correlated four-factor structure (treating Physical Symptoms and Physical Well-Being as a combined or closely correlated dual-tier somatic construct alongside Psychological, Existential, and Support domains) demonstrated superior fit compared to unidimensional or classic two-factor (purely physical vs. psychosocial) models.

Fit indices reported across empirical studies frequently achieve standard criteria:

• Comparative Fit Index (CFI) $ge 0.92$ to $0.96$
• Tucker-Lewis Index (TLI) $ge 0.90$ to $0.95$
• Root Mean Square Error of Approximation (RMSEA) $le 0.05$ to $0.07$
• Standardized Root Mean Square Residual (SRMR) $le 0.06$

These structural findings conclusively show that the existential dimension functions as an autonomous psychometric construct rather than an artifact of psychological anxiety or physical comfort.

Instrument / Measurement Tool

• Instrument Name: McGill Quality of Life Questionnaire (MQOL)
• Original Language: English (simultaneously standardized in Canadian French)
• Target Population: Adults living with life-threatening, progressive, terminal illnesses (e.g., advanced cancer, end-stage organ failure, amyotrophic lateral sclerosis, palliative care recipients)
• Administration Format: Patient self-report, structured interview by a trained interviewer, or digital electronic clinical outcome assessment (eCOA)
• Completion Time: Approximately 5 to 10 minutes
• Recall Period: Past 2 days (“OVER THE PAST 2 DAYS”)
• Structural Composition:
  • Part A: Single global item assessing overall quality of life on an 11-point numerical rating scale (0 = Very bad to 10 = Excellent).
  • Part B (Physical Domain): Instructions asking the patient to nominate up to three troublesome physical symptoms or problems experienced over the past 2 days, each rated from 1 (No problem) to 10 (Tremendous problem). Item 4 assesses general physical well-being from 1 (Physically terrible) to 10 (Physically well).
  • Part C (Psychological, Existential, Support Domains): 12 standardized items (Items 5 through 16) rated on 1 to 10 numerical rating scales with customized semantic differential anchors reflecting emotional, philosophical, and social states.
  • Part D (Optional Qualitative Component): Free-text section permitting respondents to list or describe life events or factors exerting the greatest positive or negative effect on their quality of life.
• Scoring and Transformation Protocols:
  • Standardization Directionality: Items must be scored so that a score of 10 always represents the highest (best) quality of life, while 0 (or 1) represents the lowest (worst) quality of life.
  • Reverse Scoring: Items anchored with negative endpoints on the higher numerical value must be reversed. Specifically:
    • Part B Items 1, 2, and 3: Symptoms rated 1 to 10 are reversed using the formula: $\text{Score}_{\text{reversed}} = 11 – \text{Item Score}$. (If a patient writes “none”, that item is assigned the optimal score of 10).
    • Part C Negative Affect / Distress Items (Items 5, 6, 7, 8, and 13): These items must be reversed so that low distress converts to high quality of life (Formula: $\text{Score}_{\text{reversed}} = 11 – \text{Item Score}$).
    • Positively keyed items (Items 4, 9, 10, 11, 12, 14, 15, and 16) remain unreversed.
  • Subscale Score Calculation: Each subscale score is computed as the arithmetic mean of its constituent completed items (yielding a subscale score ranging from 0 to 10):
    • Physical Symptoms Subscale: Mean of the reversed scores of patient-nominated symptoms in Part B (Items 1, 2, 3).
    • Physical Well-Being Subscale: Converted score of Item 4. (In some 4-subscale scoring models, Part B Items 1–4 are aggregated into a single Physical Domain).
    • Psychological Subscale: Mean of reversed Items 5, 6, 7, and 8.
    • Existential Subscale: Mean of Items 9, 10, 11, 12, reversed 13, and 14.
    • Support Subscale: Mean of Items 15 and 16.
  • MQOL Total Score: Calculated as the arithmetic mean of the subscale scores (or mean of all domains), yielding a summary index ranging from 0 to 10. Part A (Overall QOL) is typically evaluated as an independent marker and can be analyzed separately or included alongside subscales per specific research protocols.

Permissions & Fee and Test Year

The McGill Quality of Life Questionnaire was first published in 1995 by Dr. S. Robin Cohen, Dr. Balfour M. Mount, and colleagues. The instrument is copyrighted by McGill University and the primary developers.

The MQOL is made broadly accessible to the global clinical and academic community. It is free of charge for non-commercial research, academic inquiry, graduate training, and routine clinical care within non-profit healthcare institutions, hospice organizations, and palliative care centers. For-profit clinical trials, pharmaceutical-sponsored investigations, or commercial electronic medical record integrations may require formal licensing, standard permissions, and execution of a user agreement. Researchers and clinicians wishing to utilize or translate the questionnaire can contact Dr. S. Robin Cohen or the McGill University Department of Oncology / Palliative Care Division.

References

• Cassell, E. J. (1982). The nature of suffering and the goals of medicine. New England Journal of Medicine, 306(11), 639–645. https://doi.org/10.1056/NEJM198203183061104
• Cohen, S. R., & Mount, B. M. (1992). Quality of life in terminal illness: Defining and measuring subjective well-being in the palliative care setting. Journal of Palliative Care, 8(3), 40–45. https://doi.org/10.1177/082585979200800308
• Cohen, S. R., Mount, B. M., Strobel, M. I., & Bui, F. (1995). The McGill Quality of Life Questionnaire: A measure of quality of life appropriate for people with advanced disease. A preliminary study of validity and acceptability. Palliative Medicine, 9(3), 207–219. https://doi.org/10.1177/026921639500900306
• Cohen, S. R., Mount, B. M., Bruera, E., Provost, M., Rowe, J., & Tong, K. (1997). Validity of the McGill Quality of Life Questionnaire in the palliative care setting: A multi-centre Canadian study demonstrating the importance of the existential domain. Palliative Medicine, 11(1), 3–20. https://doi.org/10.1177/026921639701100102
• Cohen, S. R., & Mount, B. M. (2000). Living with cancer: “Good” days and “bad” days—what produces them? Cancer, 89(8), 1854–1865. https://doi.org/10.1177/0269216306072347
• Frankl, V. E. (1959). Man’s Search for Meaning: An Introduction to Logotherapy. Beacon Press.
• Mount, B. M. (1993). Whole person care: Beyond palliative care. Journal of Palliative Care, 9(1), 28–32. https://doi.org/10.1177/082585979300900107
• Robin Cohen, S., Sawatzky, R., Russell, L. B., Shahidi, J., Heyland, D. K., & Gadermann, A. M. (2017). Measuring the quality of life of people at the end of life: The McGill Quality of Life Questionnaire–Revised. Palliative Medicine, 31(2), 120–129. https://doi.org/10.1177/0269216316659603

13. Items of the Scale (Questionnaire)