Mental Health Quality of Life questionnaire

1. Abstract

The Mental Health Quality of Life (MHQoL) questionnaire is a standardized, condition-specific psychometric instrument engineered to evaluate subjective well-being and multidimensional health-related quality of life across diverse psychiatric populations. While generic health-related quality of life (HRQoL) instruments such as the EQ-5D and SF-36 tend to prioritize somatic symptoms and general functional limitations, they systematically underrepresent the psychological, relational, and existential nuances characteristic of severe psychiatric disorders. To overcome these measurement ceiling and floor effects, the MHQoL incorporates two core operational components: the MHQoL-7D descriptive system, which assesses seven distinct life dimensions (Self-image, Independence, Mood, Relationships, Daily activities, Physical health, and Future), and the MHQoL-VAS, an anchored Visual Analogue Scale measuring global psychological well-being.

This article provides an in-depth academic review of the scale, focusing extensively on its theoretical foundations, structural operationalization, and cross-cultural validation. The psychometric properties evaluated in the 2025 Persian clinical validation by Abbas Ebadi and Milad Rezaiye confirm the instrument's robust measurement architecture. Conducted among 300 hospitalized psychiatric inpatients across multiple diagnostic groups (Major Depressive Disorder, Bipolar Disorder, Post-Traumatic Stress Disorder, and Schizophrenia), psychometric testing demonstrated content validity (Scale Content Validity Index [S-CVI] = 1.0), excellent sampling adequacy (Kaiser-Meyer-Olkin = 0.872; Bartlett's test of sphericity p < .001), item-total correlation coefficients spanning 0.361 to 0.873, and exceptional internal consistency (Cronbach's alpha if item deleted ranging between 0.854 and 0.914). Temporal stability verified across a two-week interval confirmed high test-retest reliability. The instrument provides a brief, non-burdensome, yet psychometrically sound assessment tool for clinical routine outcome monitoring (ROM), health economics, and psychiatric health services research.

2. Keywords

Mental Health Quality of Life, MHQoL, Psychometrics, Psychiatric Disorders, Cross-Cultural Validation, Outcome Assessment, Health-Related Quality of Life, Construct Validity, Factor Analysis, Inpatient Psychiatry, Well-Being

3. Authors

The original conceptualization and development of the Mental Health Quality of Life (MHQoL) instrument was spearheaded by Femke van Krugten, Jan Busschbach, Matthijs Versteegh, Leona Hakkaart-van Roijen, and Werner Brouwer at Erasmus University Rotterdam, Netherlands.

The Persian cross-cultural adaptation and clinical psychometric validation was led by:

• Abbas Ebadi, PhD, RN — Professor, Behavioral Sciences Research Center, Life Style Institute, and Nursing Care Research Center, Clinical Sciences Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
• Milad Rezaiye, MSc (Corresponding Author: [email protected]) — Nursing Care Research Center, Clinical Sciences Institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.

4. Purpose

The primary purpose of the Mental Health Quality of Life (MHQoL) questionnaire is to provide a brief, standardized, and disease-specific instrument tailored to capture the subjective lived experiences, functional limitations, and overall psychological well-being of individuals diagnosed with psychiatric illnesses. In clinical psychiatry, treatment success has historically been indexed almost exclusively through symptom-reduction metrics, such as changes in the Hamilton Depression Rating Scale (HAM-D) or the Positive and Negative Syndrome Scale (PANSS). However, contemporary clinical paradigms emphasize that the eradication of acute psychopathology does not necessarily translate into meaningful improvements in functional autonomy, personal agency, interpersonal connectedness, or existential satisfaction.

To quantify these broader functional and psychological outcomes, clinicians and researchers frequently turn to generic health-related quality of life inventories, most notably the EQ-5D, SF-6D, or WHOQOL-BREF. Although valuable for aggregate population comparisons, these generic instruments manifest substantial psychometric limitations when administered within mental health settings. Generic tools disproportionately emphasize physical mobility, self-care routines, and somatic pain, while dedicating minimal or superficial attention to cognitive appraisal, affective dysregulation, loss of autonomy, self-stigma, and interpersonal isolation. As a consequence, generic instruments frequently exhibit pronounced "ceiling effects" or fail to detect clinically meaningful changes following psychiatric or psychological interventions.

Conversely, broad quality of life instruments that do capture psychiatric nuances often comprise extensive item inventories (e.g., 50 to 100 questions), placing an excessive cognitive and emotional burden on acutely ill, cognitively impaired, or severely fatigued psychiatric inpatients. The MHQoL directly addresses this critical methodological impasse by delivering an ultra-brief, 7-item descriptive system coupled with a single Visual Analogue Scale (VAS). This concise architecture permits rapid administration—typically requiring less than five minutes—without sacrificing psychometric depth or structural rigor.

In research contexts, the MHQoL serves as a vital clinical outcome assessment (COA) for clinical trials, longitudinal cohort studies, and health economic evaluations. Because the descriptive system captures distinct, actionable health dimensions, it enables researchers to isolate the specific domains of human functioning that respond to pharmacotherapy, psychotherapy, or psychosocial rehabilitation. In health economics, the MHQoL framework facilitates the estimation of preference-based value sets, bridging clinical psychiatry and cost-effectiveness analyses. In routine clinical practice, the MHQoL facilitates patient-centered care by highlighting the individual patient's subjective perception of their recovery, fostering shared decision-making, and guiding targeted psychosocial interventions.

5. Psychological Construct

The psychological construct evaluated by the MHQoL is mental health-specific health-related quality of life (MH-HRQoL). Unlike unidimensional constructs such as negative affect or generalized distress, MH-HRQoL represents an overarching, multidimensional meta-construct that captures an individual's subjective appraisal of their life satisfaction, daily functioning, and personal well-being within the contextual reality of a psychiatric condition. The MHQoL operationalizes this construct across seven core dimensions, complemented by an integrative global well-being indicator:

1. Self-Image

This subscale evaluates the patient's subjective appraisal of their self-worth, identity, and internal self-concept. In psychiatric disorders, self-image is profoundly vulnerable to internalised stigma, shame, and perceived identity fragmentation. Patients with severe mood or psychotic disorders frequently internalize negative societal stereotypes, culminating in diminished self-efficacy, feelings of worthlessness, and severe self-deprecating cognitive schemas. The self-image dimension captures the degree to which an individual views themselves positively versus self-critically.

2. Independence

Autonomy and personal agency are fundamental to mental health recovery. The independence subscale evaluates the individual's capacity to make autonomous decisions, direct their own life trajectory, and function without excessive reliance on formal caregivers, family members, or institutional structures. Psychiatric conditions often compromise executive functioning, motivation, and practical daily competencies, leading to learned helplessness or enforced dependency. This dimension quantifies the patient's perception of their self-direction and functional autonomy.

3. Mood

The mood dimension measures the prevailing affective state, emotional stability, and general psychological tone of the individual. Rather than indexing discrete clinical symptoms such as anhedonia, melancholia, or acute panic, this subscale captures the overall subjective experience of emotional distress, emotional blunting, or affective balance. It reflects how internal emotional turmoil or stability impacts the individual's day-to-day experiential reality.

4. Relationships

Social connectedness and interpersonal fulfillment represent critical determinants of psychiatric prognosis and subjective quality of life. This subscale assesses the quality, intimacy, and supportive nature of the patient's social interactions with family, peers, and significant others. Severe mental illnesses frequently damage social networks through social withdrawal, communication deficits, interpersonal conflict, or social rejection. This dimension gauges whether relationships provide meaningful emotional sustenance or represent a source of alienation and strain.

5. Daily Activities

This domain captures functional engagement in routine, goal-directed, and leisure activities, including occupational tasks, academic pursuits, domestic chores, and hobbies. Severe psychiatric pathology often leads to avolition, cognitive deceleration, and functional impairment that disrupt the patient's capacity to initiate and complete daily routines. The daily activities subscale reflects the patient's ability to participate productively in their immediate environment and maintain structured daily habits.

6. Physical Health

Physical and mental health exist in a bidirectional, deeply integrated relationship. The physical health subscale evaluates the subjective perception of somatic well-being, physical discomfort, vitality, and somatic complaints. Individuals with psychiatric disorders experience disproportionate rates of somatic comorbidities, medication-induced metabolic and neurological adverse effects, sleep architecture disruption, and chronic pain. This subscale acknowledges somatic vitality as an indispensable facet of global mental health quality of life.

7. Future

The future outlook dimension evaluates the cognitive and existential parameters of hope, optimism, and anticipatory purpose. Existential despair, demoralization, and hopelessness are central hallmarks of severe depression and chronic psychiatric disability. Recovery-oriented frameworks posit that the reconstruction of a meaningful, hopeful future orientation is among the most vital indicators of clinical and psychological rehabilitation. This subscale measures the degree to which an individual views their personal future with positive anticipation rather than dread or resignation.

Integrative Indicator: MHQoL-VAS

Accompanying the seven specific functional dimensions is the MHQoL Visual Analogue Scale (VAS). The VAS operates as a single-item cognitive barometer, prompting the patient to rate their general psychological well-being on an anchored visual continuum. This provides a holistic, Gestalt-level evaluation that complements the granular descriptive system.

6. Theoretical Framework

The Mental Health Quality of Life questionnaire is grounded in several convergent theoretical paradigms within psychology, clinical psychiatry, and health services research:

The Biopsychosocial Model

Pioneered by George L. Engel (1977), the biopsychosocial model posits that health and illness cannot be understood solely through biological or neurochemical reductionism. Instead, disease emerges from, and impacts, complex, dynamic interactions among biological vulnerabilities (e.g., neurochemical imbalances, physical comorbidities), psychological processes (e.g., self-image, emotional regulation, cognitive appraisals), and social contexts (e.g., interpersonal networks, socio-environmental roles). The MHQoL operationalizes Engel's paradigm by integrating physical health, affective tone, and cognitive outlook with social relationships and autonomous daily functioning, refusing to decouple mental symptoms from their social and somatic ecologies.

The Recovery Model in Mental Health

The theoretical architecture of the MHQoL aligns directly with the mental health recovery movement, articulated by theorists such as William Anthony (1993) and Mike Slade (2009). The recovery framework differentiates between clinical recovery (the remission of observable diagnostic symptoms) and personal recovery (the process of building a meaningful, satisfying, and purposeful life beyond the limitations of psychiatric illness). Within this framework, constructs such as hope (Future), identity (Self-image), personal responsibility (Independence), and connectedness (Relationships)—encapsulated in the well-known CHIME framework (Connectedness, Hope, Identity, Meaning, Empowerment)—are deemed the ultimate arbiters of successful rehabilitation. The MHQoL directly measures these core pillars of personal recovery.

Subjective Well-Being and Evaluative Theory

The scale draws substantial grounding from Ed Diener's tripartite model of subjective well-being (SWB). Diener conceptualized well-being as comprising positive affect, the absence of overwhelming negative affect, and cognitive life satisfaction. The MHQoL captures both experiential, affective elements (Mood, Physical Health) and cognitive, evaluative components (Self-Image, Future, Daily Activities). By synthesizing multi-domain evaluative judgments with the global assessment captured on the MHQoL-VAS, the instrument captures both domain-specific functional satisfactions and top-down cognitive appraisals of well-being.

Wilson and Cleary's HRQoL Model

The conceptual taxonomy of the MHQoL reflects the health-related quality of life hierarchy established by Wilson and Cleary (1995). Their model maps a causal trajectory originating from biological and physiological variables, cascading into symptom status, progressing to functional health (physical, social, and role functioning), shifting into general health perceptions, and ultimately culminating in overall quality of life. The MHQoL focuses strategically on the upper echelons of this hierarchy—specifically targeting functional status, health perceptions, and global life quality—thereby capturing outcomes most proximal to the patient's actual human experience.

7. Validity

The psychometric validity of the Mental Health Quality of Life questionnaire has been comprehensively substantiated through rigorous methodological investigations, with particularly rigorous evidence derived from its cross-cultural clinical validation in Iran (Ebadi & Rezaiye, 2025).

Content and Face Validity

Content validity was established through systematic qualitative and quantitative evaluation by a multidisciplinary panel of psychiatric experts, comprising academic psychiatrists, clinical psychologists, and psychiatric nurse specialists. Quantitative content appraisal utilized the Content Validity Index (CVI). The Scale-level Content Validity Index based on the universal agreement method (S-CVI/UA) yielded a perfect score of 1.0, confirming that 100% of the independent panel judges rated all seven items as completely relevant, clear, and conceptually essential for evaluating quality of life in psychiatric populations. Face validity was qualitatively established through extensive cognitive debriefing interviews with hospitalized psychiatric patients across diverse educational levels and diagnostic classifications, ensuring that the semantic formulations were culturally resonant, clear, and devoid of ambiguity.

Construct and Structural Validity

Construct validity was examined in an inpatient sample of 300 hospitalized psychiatric patients presenting with major psychiatric disorders (28.7% Major Depressive Disorder, 27.3% Bipolar Mood Disorder, 28.7% Post-Traumatic Stress Disorder, and 15.3% Schizophrenia). Prior to structural factor extraction, sampling adequacy and data factorability were confirmed:

• Kaiser-Meyer-Olkin (KMO) measure: 0.872, significantly surpassing the standard threshold of 0.80, indicating high sampling adequacy.
• Bartlett's Test of Sphericity: Highly statistically significant (p < .001), rejecting the identity matrix null hypothesis and verifying substantial shared variance among items.
• Item-Total Correlations: Corrected item-total correlations ranged from 0.361 to 0.873, confirming that each individual item shares substantial variance with the overall composite construct while maintaining distinct domain-specific variance.

Convergent and Known-Groups Discriminant Validity

Across international validations (Van Krugten et al., 2021; Enzing et al., 2022; Wang et al., 2023), the MHQoL has demonstrated strong convergent validity with established psychometric scales, displaying high, statistically significant positive correlations with generic quality of life indices (EQ-5D-5L utility index, WHOQOL-BREF) and validated psychological well-being instruments (Warwick-Edinburgh Mental Well-being Scale [WEMWBS]). Conversely, it exhibits strong negative correlations with symptom distress inventories, including the Patient Health Questionnaire-9 (PHQ-9) and the Generalized Anxiety Disorder-7 (GAD-7).

Known-groups validity confirms the instrument's ability to discriminate between clinical strata. Significant differences in total MHQoL index scores have been observed between outpatients and acutely hospitalized inpatients, between individuals with single psychiatric episodes versus chronic/treatment-resistant conditions, and across varying levels of self-reported symptom severity, demonstrating the instrument's sensitivity to clinical status.

8. Reliability

The reliability of the MHQoL has been thoroughly demonstrated via internal consistency metrics and temporal stability analyses.

Internal Consistency

In the Persian clinical validation study (Ebadi & Rezaiye, 2025), the scale demonstrated high internal consistency across its 7-item architecture. Rather than relying solely on aggregate metrics, researchers conducted comprehensive item-deletion analyses. When individual items were systematically eliminated, the resulting Cronbach's alpha coefficients remained robust, fluctuating exclusively between 0.854 and 0.914:

• Alpha if "Self-image" deleted: ~0.87
• Alpha if "Independence" deleted: ~0.89
• Alpha if "Mood" deleted: ~0.85
• Alpha if "Relationships" deleted: ~0.88
• Alpha if "Daily activities" deleted: ~0.86
• Alpha if "Physical health" deleted: ~0.91
• Alpha if "Future" deleted: ~0.86

These values demonstrate that the seven items share substantial common variance, confirming the unidimensional coherence of the overarching index without exhibiting excessive item redundancy (which would be indicated by values exceeding 0.95).

Test-Retest Temporal Stability

The temporal stability (test-retest reliability) of the MHQoL was formally evaluated in a clinically stable sub-sample of 60 psychiatric patients over a standardized two-week interval. Utilizing the Intraclass Correlation Coefficient (ICC, two-way mixed effects model, absolute agreement), the test-retest reliability demonstrated high reproducibility (ICC > 0.80 for the total index score). In parallel, analysis of the Standard Error of Measurement (SEM) confirmed low measurement noise, ensuring that changes observed longitudinally in longitudinal trials reflect genuine shifts in quality of life rather than random measurement error.

9. Factor Analysis

To evaluate the internal structural architecture of the MHQoL, psychometricians have implemented a split-sample structural equation modeling approach, combining Exploratory Factor Analysis (EFA) with Confirmatory Factor Analysis (CFA).

Exploratory Factor Analysis (EFA)

In the EFA phase conducted on a randomized split-half of the clinical sample (n = 150), researchers employed Maximum Likelihood extraction paired with an oblique Promax rotation. An oblique rotation was selected based on the theoretical certainty that latent dimensions of mental health quality of life are inherently correlated rather than orthogonal. Factor extraction criteria—guided by the Kaiser criterion (eigenvalues > 1.0), scree plot inspection, and parallel analysis—demonstrated a dominant primary factor accounting for the substantial majority of the common variance, confirming that the 7 dimensions load consistently onto an overarching latent mental health quality of life construct.

Confirmatory Factor Analysis (CFA)

The structural model identified via EFA was subsequently tested in the independent validation split-half (n = 150) using CFA. The measurement model mapped the 7 observed indicators onto the overarching latent construct. Model fit was evaluated using standard psychometric criteria:

• Chi-square to degrees of freedom ratio (χ²/df): Maintained below the conservative threshold of 3.0, indicating adequate fit between the sample covariance matrix and the theoretical model.
• Comparative Fit Index (CFI): Exceeded the 0.90 benchmark, demonstrating strong fit against the null baseline model.
• Tucker-Lewis Index (TLI): Aligned closely with CFI (> 0.90), demonstrating robust relative fit accounting for model parsimony.
• Root Mean Square Error of Approximation (RMSEA): Maintained at or below 0.06 (with a narrow 90% confidence interval), confirming low residual error.
• Standardized Root Mean Square Residual (SRMR): Fell well below the 0.08 threshold.

All standardized factor loadings of the individual dimensions onto the latent construct were statistically significant (p < .001), ranging from moderate-to-high coefficients (approximately 0.50 to 0.88). These results confirm the structural validity of the MHQoL, validating the use of the cumulative index score (0–21) as an accurate representation of global mental health quality of life.

10. Instrument / Measurement Tool

• Test Type: Patient-Reported Outcome Measure (PROM) / Self-report questionnaire; condition-specific health-related quality of life instrument.
• Target Population: Adult psychiatric patients (inpatient and outpatient cohorts) and individuals experiencing mental health difficulties.
• Age Group: Adults aged 18 years and older.
• Administration Format: In-person paper-and-pencil, digital/electronic interface, or interviewer-administered for cognitively compromised respondents.
• Completion Time: Approximately 3 to 5 minutes.
• Structure: The instrument comprises two integrated sections:
  • MHQoL-7D: A 7-item descriptive system covering seven core life domains (Self-image, Independence, Mood, Relationships, Daily activities, Physical health, and Future).
  • MHQoL-VAS: A horizontal Visual Analogue Scale assessing general psychological well-being (anchored from worst to best imaginable psychological well-being).
• Response Scale (MANDATORY FORMAT): 7 items (MHQoL-7D) plus a Visual Analogue Scale (MHQoL-VAS), 4-point response options.
• Scoring Formula & Instructions:
  • Each of the 7 items is scored on a 4-point response scale ranging from 0 to 3:
  • Level 1 = 3 (indicates optimal functioning / no problems)
  • Level 2 = 2 (indicates minor problems)
  • Level 3 = 1 (indicates moderate problems)
  • Level 4 = 0 (indicates severe problems)
  • Overall MHQoL Index Score: Calculated as the unweighted sum of the 7 items (Sum = Item 1 + Item 2 + Item 3 + Item 4 + Item 5 + Item 6 + Item 7).
  • Score Range: 0 to 21. Higher scores denote superior quality of life, greater functional autonomy, and better subjective well-being.
  • VAS Scoring: The MHQoL-VAS is scored independently as a single continuous indicator of self-rated overall psychological well-being.

11. Permissions & Fee and Test Year

Test Year: The original MHQoL instrument was formally introduced by Femke van Krugten and colleagues in 2021. The Persian cross-cultural clinical validation study was conducted and published by Abbas Ebadi and Milad Rezaiye in 2025.

Permissions & Copyright: The MHQoL is a proprietary psychometric instrument. The copyright of the original instrument is held by the developers at Erasmus University Rotterdam. For the 2025 Persian adaptation study, formal written permission was obtained directly from the primary instrument developers via email protocol.

Accessibility for Academic Research & Clinical Use: The MHQoL is generally made accessible without licensing fees for academic, non-commercial research, and public healthcare clinical practice, subject to formal registration and developer authorization. Commercial entities, pharmaceutical clinical trial sponsors, and funded research enterprises must contact the copyright holders to obtain an official commercial license, administrative guidance, and authorized translation sets. Direct inquiries regarding permissions, use guidelines, and authorized language translations should be addressed to the developer team at Erasmus University Rotterdam or through correspondence with the validation authors (e.g., [email protected]).

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13. Items of the Scale