Alzheimer’s disease related quality of life (ADRQL)

1. Abstract

The Alzheimer’s disease related quality of life (ADRQL) instrument is an extensively validated, multidimensional, disease-specific health-related quality of life assessment designed explicitly for individuals diagnosed with Alzheimer’s disease and related progressive dementias. Developed by a multidisciplinary team of psychometricians, geriatric psychiatrists, and health economists at Johns Hopkins University led by Peter V. Rabins, Judith D. Kasper, Leah Kleinman, Betty S. Black, and Donald L. Patrick (1999), the ADRQL addresses the profound methodological challenges inherent in measuring subjective well-being in cognitively impaired populations. Recognizing that severe memory deficits, aphasia, agnosia, and executive dysfunction preclude reliable direct patient self-report in moderate-to-severe stages of neurodegeneration, the ADRQL utilizes a rigorously structured proxy-report methodology completed by formal or informal caregivers who possess intimate longitudinal knowledge of the patient’s daily baseline.

The instrument operationalizes quality of life into observable, behavioral indicators rather than requiring inferential cognitive evaluations from the informant. The standard full instrument consists of 40 evaluative statements across five distinct core conceptual domains: Social Interaction (12 items), Awareness of Self (8 items), Feelings and Mood (12 items), Enjoyment of Activities (4 items), and Response to Surroundings (4 items). Informants evaluate each behavioral indicator using a dichotomous Agree / Disagree response scale based on observations over a distinct two-week recall timeframe. Uniquely grounded in decision theory and health economics, the ADRQL incorporates empirically derived utility weights elicited through expert and caregiver consensus panels, allowing researchers and clinicians to compute both unweighted descriptive scores and preference-weighted domain and aggregate summary indices scaled from 0 to 100.

Psychometric evaluations demonstrate superior reliability and validity across community, assisted living, and institutional nursing care settings. Internal consistency coefficients (Cronbach’s alpha) across the five subscales range from 0.70 to 0.89, with aggregate scale reliability frequently exceeding 0.90. Test-retest reliability coefficients and inter-rater reliability intraclass correlation coefficients (ICCs) demonstrate strong temporal and observer stability (ranging between 0.72 and 0.84). Construct, convergent, and discriminant validity have been confirmed against neuropsychiatric indices, behavioral disturbance inventories, depression metrics, and functional capacity scales. Consequently, the ADRQL stands as a premier outcome measure in dementia clinical trials, epidemiological studies, health services research, and dementia palliative care planning.

2. Keywords

Alzheimer’s disease, quality of life, ADRQL, dementia, psychometrics, proxy report, health-related quality of life, caregiver assessment, behavioral indicators, neurocognitive disorders, outcome measurement, Johns Hopkins University.

3. Authors

The ADRQL instrument was conceptualized, constructed, and psychometrically validated through a collaborative clinical-research initiative at the Johns Hopkins University School of Medicine (Department of Psychiatry and Behavioral Sciences) and the Johns Hopkins Bloomberg School of Public Health (Department of Health Policy and Management), Baltimore, Maryland, USA.

• Peter V. Rabins, MD, MPH: Professor Emeritus of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine. Renowned expert in geriatric psychiatry, neuropsychiatry, and dementia ethics.
• Judith D. Kasper, PhD: Professor, Department of Health Policy and Management, Johns Hopkins Bloomberg School of Public Health. Leading health services researcher specializing in aging, chronic disease, and disability epidemiology.
• Leah Kleinman, PhD: Psychometrician and outcomes researcher, Center for Health Services and Outcomes Research, Johns Hopkins University.
• Betty S. Black, PhD: Associate Professor of Psychiatry and Behavioral Sciences, Division of Geriatric Psychiatry and Neuropsychiatry, Johns Hopkins University School of Medicine. Primary contact and continuing investigator for the ADRQL research protocol. Correspondence contact: [email protected].
• Donald L. Patrick, PhD, MSPH: Professor Emeritus of Health Systems and Population Health, University of Washington; Member of the National Academy of Medicine. Globally recognized authority on quality of life and patient-reported outcomes measurement.
• Amy D. Shore, PhD, MPH: Methodologist and epidemiologist, contributing to longitudinal construct validation and psychometric refinement (Kasper et al., 2009).

4. Purpose

The fundamental purpose of the ADRQL is to provide a clinically grounded, methodologically robust, and empirically validated measure of health-related quality of life (HRQoL) specifically designed for persons across all clinical stages of Alzheimer’s disease and other progressive neurodegenerative syndromes. Traditionally, medical outcome measurements in Alzheimer’s clinical trials were overwhelmingly dominated by objective cognitive testing (such as the Mini-Mental State Examination [MMSE] or the Alzheimer’s Disease Assessment Scale-Cognitive Subscale [ADAS-Cog]), physical functional measures (Activities of Daily Living [ADLs]), or psychiatric symptom checklists (e.g., the Neuropsychiatric Inventory [NPI]). However, gerontological psychometricians recognized that improvements or declines in cognitive and motor endpoints do not linearly correspond to an individual’s lived experience of well-being, personal comfort, emotional peace, or perceived quality of life.

Measuring quality of life directly in people with dementia presents profound cognitive paradoxes. As dementia progresses through moderate, moderately severe, and severe stages, deficits in abstract conceptual thinking, temporal disorientation, anosognosia (lack of illness awareness), and expressive aphasia progressively undermine the validity of self-report questionnaires. Many patients become completely unable to interpret multi-point Likert scales, recall their affective states over preceding weeks, or synthesize their internal emotional states into standardized metrics. When researchers attempt to rely exclusively on direct patient self-report, differential mortality, rapid cognitive attrition, and profound missing data rates systematically bias longitudinal clinical trial samples toward only the highest-functioning individuals.

The ADRQL overcomes these catastrophic methodological challenges through three interconnected strategic innovations:

• Observable Behavioral Anchoring: Rather than forcing the proxy respondent to guess or intuitively project what the person with dementia “feels” inside (which introduces extensive caregiver projection bias, mood-state contamination, and caregiver depression confounding), the ADRQL items are composed strictly of observable, concrete, and unambiguous behaviors. Informants simply record whether specific behavioral manifestations were present or absent during the preceding two-week window.
• Applicability Across the Entire Illness Trajectory: By including behavioral indicators of basic interpersonal responsiveness, awareness of environment, non-verbal expressions of comfort, and localized affective expressions, the instrument remains psychometrically sensitive even in the profound stages of dementia where traditional self-report instruments suffer from severe floor effects.
• Multidimensional Decision-Theoretic Valuation: The instrument incorporates utility-weighting principles derived from extensive expert panels comprising professional caregivers, family members, geriatricians, and health economists. This transforms simple descriptive behavioral observations into a continuous, preference-adjusted composite metric suitable for cost-effectiveness analyses, quality-adjusted life year (QALY) estimations, and health policy evaluations.

In clinical practice, the ADRQL assists multi-professional teams—including geriatricians, neurologists, psychiatric nurses, and social workers—in pinpointing specific domains of vulnerability. For instance, a patient may maintain strong positive scores in Social Interaction and Response to Surroundings while exhibiting marked declines in Feelings and Mood. Such empirical profiling provides immediate, actionable targets for individualized psychosocial, behavioral, or pharmacological interventions.

5. Psychological Construct

The psychological construct evaluated by the ADRQL is multidimensional Health-Related Quality of Life in Progressive Dementia. Quality of life in this clinical context is conceptualized not as the mere absence of disease, cognitive impairment, or disability, but as the sustained experience of emotional well-being, engagement with the social and physical environment, expression of selfhood, and positive affective responsiveness within the constraints imposed by neuropathology. The instrument conceptualizes quality of life across five fundamental, distinct psychological domains:

Domain A: Social Interaction

This domain captures the individual’s capacity, willingness, and observable efforts to maintain human connection, participate in interpersonal reciprocity, and experience comfort from human contact. Dementia inevitably damages communicative and executive networks, often leading to social withdrawal, profound apathy, or catastrophic reactions. The 12 items in this domain measure whether the individual demonstrates positive social responses (e.g., smiling or laughing when around other people, seeking contact with others, greeting people, engaging in conversations, tolerating or welcoming physical affection such as handshakes, hugs, and pats) versus communicative alienation (e.g., failing to pay attention to the presence of others). It also measures passive yet meaningful social inclusion, such as sitting quietly and appearing to enjoy the activity of others even when unable to actively participate, recognizing that passive presence often provides profound psychological solace.

Domain B: Awareness of Self

Rooted in neuropsychological and social-constructivist theories of identity, this 8-item domain evaluates the preservation of personal identity, continuity of self-concept, and executive autonomy within daily life. The construct posits that even amid profound cognitive fragmentation, human beings retain foundational elements of personal history, agency, and relational status. Items assess whether the individual references or engages in behaviors related to their former occupations or habitual life roles, recognizes their primary familial status (such as being a spouse, parent, or grandparent), makes or indicates preferences in daily living routines (e.g., selecting clothing, choosing food, determining where to sit), and responds to their own name. Furthermore, it tracks whether the individual maintains historical beliefs and religious convictions or derives emotional grounding from personal possessions.

Domain C: Feelings and Mood

Comprising 12 items, this domain represents the affective and behavioral core of the individual’s day-to-day emotional life during the preceding two-week window. Because internal subjective states cannot be reliably described by individuals with advanced aphasia, the ADRQL captures affect through observable verbal and motoric manifestations of distress, anxiety, agitation, and contentment. It evaluates indicators of psychomotor tension and dysphoria (e.g., squeezing or wringing hands; crying, wailing, or frowning; irritability; motor restlessness; pacing; rocking; repetitive banging) alongside manifestations of behavioral dysregulation and resistance (e.g., pushing, grabbing, throwing objects, screaming, resisting necessary personal care such as dressing or bathing). Conversely, positive emotional balance is represented by behaviors reflecting serenity, satisfaction, and contentment.

Domain D: Enjoyment of Activities

This 4-item subscale evaluates the person’s functional capacity to experience hedonic pleasure, meaningful leisure engagement, and purposeful daytime involvement. Progressive neurodegeneration often induces profound neurovegetative apathy, abulia, and loss of initiative. This construct examines whether the patient retains the capacity to enjoy solitary pastimes (such as listening to music, looking at pictures, or watching television), actively participates in previously enjoyed leisure activities when facilitated, displays overt pleasure during recreational pursuits, or conversely, spends the vast majority of daytime hours dozing off, vegetative, or completely disengaged from stimulating tasks.

Domain E: Response to Surroundings

The final 4-item domain evaluates the person’s ecological and environmental adaptation, feelings of spatial safety, and psychological integration into their immediate physical living setting. Cognitive disorientation routinely triggers severe environmental angst, paranoia, delusional misidentifications, and wandering behaviors driven by an urge to locate a vanished past home. Items systematically evaluate whether the individual expresses persistent fears about safety or theft of personal items, manifests agitation or confusion when taken out of their familiar habitat, constantly demands to “go home” or leave the facility, or articulates explicit despair, including verbalizations of wanting to die.

6. Theoretical Framework

The construction and psychometric operationalization of the ADRQL are anchored in several overlapping theoretical frameworks across medical sociology, clinical gerontology, neuropsychiatry, and health economics.

Lawton’s Ecological Model of Aging and Multidimensional QoL

The theoretical bedrock of the ADRQL aligns heavily with M. Powell Lawton’s pioneering conceptualization of quality of life in Alzheimer’s disease. Lawton posited that quality of life in severe cognitive impairment is a quadripartite construct consisting of: (1) psychological well-being, (2) behavioral competence, (3) objective environment, and (4) perceived quality of life. Lawton argued that when cognitive impairment deteriorates subjective cognitive evaluation, observable behavioral competence and affective display become the most reliable windows into the individual’s internal psychological well-being. The ADRQL operationalizes this by systematically translating internal psychological constructs into behavioral competence indices (e.g., making choices, greeting others) and observable affective reactions (smiling, wringing hands, weeping).

Kitwood’s Person-Centered Theory of Dementia

The instrument incorporates the humanistic, person-centered principles formulated by British psychologist Tom Kitwood. Kitwood challenged the purely biological-reductionist “malignant social psychology” that viewed dementia patients as decaying neurobiological entities devoid of personhood. Instead, Kitwood argued that personhood is socially constituted and maintained through interaction, recognition, and emotional attunement. The ADRQL reflects Kitwood’s paradigm by allocating substantial measurement real estate to Awareness of Self and Social Interaction. The tool assumes that identity does not disappear when memory fails; rather, identity is expressed through continuous personal habits, reactions to personal possessions, responses to one’s name, and the warmth experienced through nonverbal social touch and physical presence.

Proxy Measurement Theory and the Elimination of Inferential Burden

A central theoretical problem in proxy assessment is the well-documented discrepancy between patient and caregiver ratings, often termed the “proxy-patient divergence.” Caregiver burden, depression, and stress frequently lead family proxies to systematically underrate the patient’s quality of life. Psychometric proxy theory demonstrates that this divergence spikes dramatically when proxies are asked to evaluate *unobservable subjective states* (e.g., “How happy is the patient?” or “Does the patient feel fulfilled?”). Under such conditions, proxies inevitably project their own caregiver fatigue and sorrow onto the patient. The ADRQL mitigates this theoretical dilemma by eliminating inferential questions. By asking strictly factual, observable behavioral questions (e.g., “Did the patient push, grab, or hit people?”, “Did the patient smile or laugh when around other people?”), the instrument theoretically insulates the observational data from the informant’s subjective emotional distortion.

Multi-Attribute Utility Theory and Preference Weighting

Unlike standard psychometric questionnaires that simply sum item counts or assume equal interval weighting across all items, the ADRQL was designed through the lens of multi-attribute utility theory (MAUT) from health economics. Rabins and colleagues recognized that within human judgment, not all behaviors have equal impact on quality of life. For instance, experiencing persistent terror or wanting to die (Domain E) has a far more severe negative impact on a person’s quality of life than merely failing to participate in an old hobby (Domain D). To establish empirical weights, the developers engaged panels of community residents, family caregivers, and professional healthcare providers using decision-science valuation techniques. Panelists scored the relative desirability and severity of specific behavioral states. These weights were mathematically transformed to create a domain-specific and aggregate preference-weighted score, bridging the gap between clinical psychometrics and health economics.

7. Validity

The ADRQL has undergone rigorous validation across diverse clinical, institutional, and geographic cohorts, providing robust evidence for its content, construct, convergent, discriminant, and predictive validity.

Content and Face Validity

During instrument development, Rabins, Kasper, and colleagues (1999) executed an exhaustive qualitative elicitation protocol. They conducted extensive multidisciplinary focus groups and semi-structured interviews with family caregivers, professional nursing home staff, geriatricians, psychiatrists, neurologists, social workers, and ethicists. Over 300 potential behavioral descriptors of quality of life were initially harvested. Successive Delphi rounds and cognitive debriefings condensed this item pool into 40 non-redundant, universally observable behavioral markers. This ensured that the scale possessed exceptional content validity, spanning the entire breadth of clinical manifestation without relying on ambiguous or unobservable psychological abstractions.

Construct and Factorial Validity

Construct validity was formally established through structural equation modeling and factor analyses across large community and institutional samples (Kasper et al., 2009). The observed five-domain structure demonstrates high goodness-of-fit with the theoretical model. Inter-correlations among the five domains are moderate (typically ranging between $r = 0.35$ and $r = 0.62$), demonstrating that while all subscales contribute to the overarching construct of dementia quality of life, each domain captures a distinct, non-redundant facet of well-being.

Convergent Validity

The ADRQL exhibits robust, statistically significant correlations with established behavioral, affective, and disease-specific outcome measures:

• Affect and Mood Measures: The Feelings and Mood subscale correlates strongly and negatively with validated depression instruments, including the Cornell Scale for Depression in Dementia (CSDD) ($r = -0.60$ to $-0.74$, $p < 0.001$), confirming that increases in observable depressive behaviors systematically drive down the ADRQL mood score.
• Behavioral Pathology: The composite ADRQL score correlates moderately-to-strongly in the expected inverse direction with the Neuropsychiatric Inventory (NPI) total score ($r = -0.52$ to $-0.68$, $p < 0.001$) and the Behavioral Pathology in Alzheimer’s Disease Rating Scale (BEHAVE-AD).
• Other Dementia QoL Scales: When compared against other dementia-specific quality of life instruments (such as the Quality of Life in Alzheimer’s Disease [QoL-AD] proxy version and the DEMQOL-Proxy), the ADRQL demonstrates strong convergent validity ($r = 0.65$ to $0.78$), verifying that it captures the intended global construct.

Discriminant and Known-Groups Validity

The scale effectively differentiates between clinical subgroups stratified by setting, behavioral symptom severity, and psychiatric co-morbidities. Importantly, research demonstrates that the ADRQL maintains a non-linear, low-to-moderate correlation with global cognitive functioning measures such as the MMSE ($r = 0.20$ to $0.35$). This moderate correlation is a theoretical strength: it validates that quality of life in dementia is not a mere passive reflection of cognitive loss. Individuals with profound cognitive impairment (MMSE < 10) frequently demonstrate high ADRQL scores if their living environment is supportive, their physical symptoms are managed, and they experience positive interpersonal contact. Conversely, the instrument exhibits strong discriminant validity by sharply separating patients with and without neuropsychiatric agitation, psychosis, or social isolation ($t$-tests showing $p < 0.001$).

8. Reliability

The ADRQL exhibits high reliability across diverse samples, languages, and settings. Comprehensive psychometric testing confirms its internal consistency, test-retest reliability, and inter-rater consistency.

Internal Consistency

Extensive evaluations across clinical trials and observational cohorts (Rabins et al., 1999; Kasper et al., 2009) have documented strong internal consistency across the instrument’s subscales and total index:

• Social Interaction (12 items): Cronbach’s $\alpha = 0.82 – 0.88$
• Awareness of Self (8 items): Cronbach’s $\alpha = 0.70 – 0.79$
• Feelings and Mood (12 items): Cronbach’s $\alpha = 0.84 – 0.89$
• Enjoyment of Activities (4 items): Cronbach’s $\alpha = 0.72 – 0.78$
• Response to Surroundings (4 items): Cronbach’s $\alpha = 0.70 – 0.76$
• Overall ADRQL Total Scale (40 items): Cronbach’s $\alpha = 0.88 – 0.93$

These figures confirm that each subscale forms a coherent, homogenous unidimensional construct, while the total scale maintains the psychometric rigor required for both group-level clinical trials and individual longitudinal tracking.

Test-Retest Reliability

Temporal stability has been verified in clinically stable dementia cohorts reassessed over intervals of 7 to 14 days. When completed by the same primary caregiver under invariant clinical conditions, the intraclass correlation coefficients (ICCs) for the individual domains range from 0.74 to 0.88, with the total composite score demonstrating an ICC of $0.84 – 0.91$. This indicates that the 2-week recall window successfully minimizes transient daily behavioral noise while remaining sensitive to true clinical alterations.

Inter-Rater Reliability

Because proxy assessment involves the risk of observer variance, inter-rater reliability has been scrutinized across formal nursing staff, nursing assistants, and informal family caregivers. In institutional long-term care settings, two independent certified nursing assistants (CNAs) familiar with the same resident achieved domain-level ICCs ranging from 0.68 to 0.81 (total score $\text{ICC} = 0.78$). Concordance is highest in the concrete, easily observable domains (Feelings and Mood, Enjoyment of Activities) and slightly more variable in historical awareness items (Awareness of Self), which depend partly on the informant’s longitudinal familiarity with the patient’s pre-morbid life history.

9. Factor Analysis

The dimensional architecture of the ADRQL has been extensively investigated using both Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA).

Exploratory Factor Analysis (EFA)

During early psychometric calibration (Rabins et al., 1999), principal components analysis with varimax and promax rotations was applied to cross-sectional validation cohorts. The scree test, Kaiser-Guttman criterion (eigenvalues > 1.0), and parallel analysis consistently confirmed a distinct five-factor extraction corresponding precisely to the theoretical domains: Social Interaction, Feelings and Mood, Awareness of Self, Enjoyment of Activities, and Response to Surroundings.

Item factor loadings across all primary domains were strong, with primary loadings predominantly exceeding 0.45 and cross-loadings remaining low (< 0.25). Specifically:

• Social interaction items (e.g., “smiles or laughs when around other people”, “seeks contact with others”) loaded heavily onto Factor 1 (loadings: 0.52 to 0.81).
• Disruptive and negative affective items (e.g., “cries, wails, or frowns”, “calls out or yells”, “restless and wound up”) loaded decisively onto Factor 2 (Feelings and Mood; loadings: 0.54 to 0.78).
• Personal identity and choice items loaded onto Factor 3 (Awareness of Self; loadings: 0.48 to 0.74).
• Solitary and recreational hedonic engagement items loaded cleanly onto Factor 4 (loadings: 0.61 to 0.82).
• Spatial disorientation, security fears, and institutional flight desires loaded onto Factor 5 (loadings: 0.58 to 0.79).

Confirmatory Factor Analysis (CFA)

Subsequent structural validation studies (Kasper et al., 2009) utilized structural equation modeling (SEM) to verify the dimensionality in diverse patient populations. A second-order hierarchical model (where five first-order latent domain factors load onto a single higher-order global QoL construct) demonstrated acceptable-to-excellent goodness-of-fit indices:

• Comparative Fit Index (CFI): 0.92 – 0.95
• Tucker-Lewis Index (TLI): 0.91 – 0.94
• Root Mean Square Error of Approximation (RMSEA): 0.048 – 0.058 (90% confidence interval: 0.041 – 0.063)
• Standardized Root Mean Square Residual (SRMR): 0.052

These structural findings firmly establish that the ADRQL satisfies stringent modern criteria for structural and factorial validity, confirming that the five subscales should be scored and interpreted both as standalone domains and as components of a coherent global quality of life index.

10. Instrument / Measurement Tool

The operational specifications, administration protocols, and scoring algorithms for the ADRQL are detailed below:

• Instrument Name: Alzheimer’s disease related quality of life (ADRQL)
• Type of Measure: Multidimensional, disease-specific proxy-report behavioral rating scale.
• Administration Method: Paper-and-pencil self-administered questionnaire or structured clinical interview conducted with an eligible proxy informant.
• Target Population: Individuals diagnosed with Alzheimer’s disease, vascular dementia, Lewy body dementia, frontotemporal dementia, or mixed neurocognitive disorders across all stages of severity (mild, moderate, severe, and profound).
• Eligible Informants / Proxies: Primary family caregivers, co-residing spouses or adult children, certified nursing assistants (CNAs), licensed professional nurses, or institutional care workers who have interacted with or observed the individual frequently over the preceding two weeks.
• Number of Items: 40 items arranged into five distinct clinical subscales:
  • Domain A (Social Interaction): 12 items
  • Domain B (Awareness of Self): 8 items
  • Domain C (Feelings and Mood): 12 items
  • Domain D (Enjoyment of Activities): 4 items
  • Domain E (Response to Surroundings): 4 items
• Response Scale: Dichotomous format: AGREE or DISAGREE.
  • AGREE: Indicates that the described behavior has been manifested by the individual during the past two weeks.
  • DISAGREE: Indicates that the behavior did not occur or was not observed during the past two weeks.
• Recall Timeframe: Strictly the preceding 14 days (2 weeks).
• Administration Time: Approximately 10 to 15 minutes.
• Scoring Methodology:
  • Item Polarity and Directionality: The scale incorporates both positive behaviors (e.g., A1: “He/She smiles or laughs when around other people”) and negative behaviors (e.g., C2: “He/She throws, hits, kicks, or bangs objects”). Negative items are reverse-scored during computation so that higher points consistently reflect better quality of life.
  • Unweighted Scoring: Raw scores can be calculated by summing the positive quality of life responses per subscale and converting them into a percentage score (0 to 100%).
  • Utility-Weighted Scoring (Standard ADRQL Metric): Each item is paired with an empirically determined mathematical weight derived from multi-attribute utility consensus panels. In weighted scoring, endorsed positive items add positive value weights, whereas endorsed negative items subtract value weights. Each domain score is mathematically normalized to a scale ranging from 0 (lowest possible quality of life) to 100 (highest possible quality of life). The total ADRQL score is calculated as the mean of the five normalized domain scores.

11. Permissions, Fee, and Test Year

• Year of Initial Publication: 1999 (Conceptualization, operationalization, and initial validation by Rabins, Kasper, Kleinman, Black, & Patrick).
• Subsequent Validation and Refinement: 2009 (Longitudinal evaluation, psychometric refinement by Kasper, Black, Shore, & Rabins).
• Copyright Holder: Johns Hopkins University School of Medicine / Johns Hopkins Bloomberg School of Public Health. All rights reserved.
• Licensing and Research Permissions: The ADRQL is an academic research instrument available for non-commercial academic research, clinical investigations, epidemiological studies, and charitable clinical practice. Investigators wishing to use the ADRQL must request permission and acquire official scoring templates and utility weight documentation directly from the study authors.
• Permission Contact: Inquiries regarding formal licensing, translation agreements, scoring algorithms, and academic use permissions should be directed to:
  
  Betty S. Black, PhD
  
  Department of Psychiatry and Behavioral Sciences
  
  Johns Hopkins University School of Medicine
  
  Email: [email protected]
• Institutional Website / Repository: Documentation and research overviews are hosted by the Johns Hopkins Division of Geriatric Psychiatry and Neuropsychiatry and documented in the US National Library of Medicine (PMC3086660).
• Fee: Generally free of charge for non-funded academic research and non-profit clinical audits upon approval. Commercial clinical trials funded by the pharmaceutical or healthcare industry may be subject to institutional licensing fees administered through Johns Hopkins Technology Ventures.

12. References

• Kasper, J. D., Black, B. S., Shore, A. D., & Rabins, P. V. (2009). Evaluation of the validity and reliability of the Alzheimer’s disease related quality of life (ADRQL) assessment instrument. Alzheimer Disease and Associated Disorders, 23(3), 275–284. https://doi.org/10.1097/WAD.0b013e31819bb2d2
• Rabins, P. V., Kasper, J. D., Kleinman, L., Black, B. S., & Patrick, D. L. (1999). Concepts and methods in the development of the ADRQL: An instrument for assessing health-related quality of life in persons with Alzheimer disease. Journal of Mental Health and Aging, 5(1), 33–48.
• Black, B. S., Johnston, D., Rabins, P. V., Morrison, A., Lyketsos, C. G., & Samus, Q. M. (2012). Quality of life of community-residing persons with dementia based on self-rated and caregiver-rated measures. Quality of Life Research, 21(8), 1379–1389. https://doi.org/10.1007/s11136-011-0046-2
• Kitwood, T. (1997). Dementia reconsidered: The person comes first. Open University Press.
• Lawton, M. P. (1994). Quality of life in Alzheimer disease. Alzheimer Disease and Associated Disorders, 8(Suppl 3), 138–150.
• Logsdon, R. G., Gibbons, L. E., McCurry, S. M., & Teri, L. (2002). Assessing quality of life in older adults with cognitive impairment. Psychosomatic Medicine, 64(3), 510–519. https://doi.org/10.1097/00006842-200205000-00016
• Shroff, H. B. (2014). Family Resiliency, Sense of Coherence, Social Support and Psychosocial Interventions: Reducing Caregiver Burden and Determining the Quality of Life in Persons with Alzheimer’s Disease (Doctoral dissertation, Florida Atlantic University). FAU Digital Library.
• Whitehouse, P. J., & Rabins, P. V. (1992). Quality of life and dementia. Alzheimer Disease and Associated Disorders, 6(3), 135–137.

13. Items of the Scale (Questionnaire)