Caregiver’s Burden Scale (CBS)

1. Abstract

The Caregiver’s Burden Scale (CBS), originally conceptualized and published as the Burden Interview by Steven H. Zarit, Karen E. Reever, and Julie Bach-Peterson in 1980, stands as one of the most foundational, widely cited, and clinically utilized psychometric instruments in gerontology, behavioral medicine, and clinical neuropsychology. Developed to quantify the subjective distress, physical strain, emotional exhaustion, social disruption, and financial hardship experienced by informal caregivers—particularly those caring for elderly relatives suffering from dementia and cognitive disorders—the instrument operationalizes subjective caregiving burden as a multidimensional construct. Over its developmental trajectory, the scale evolved from an initial 29-item interview-based schedule tailored for spouse caregivers into the standardized 22-item self-report questionnaire widely known as the Zarit Burden Interview (ZBI), alongside extended variants encompassing the full 29-item item bank. Items are rated on a 5-point Likert scale ranging from 0 (Never) to 4 (Nearly always). Extensive psychometric evaluations across global clinical populations have confirmed high internal consistency (Cronbach’s alpha typically ranging from .87 to .93), robust test-retest stability (coefficients ranging from .71 to .91), and robust convergent validity with measures of caregiver depression, perceived stress, anxiety, and somatic symptomatology. Structural investigations frequently identify a dominant general burden dimension accompanied by multidimensional subfactors, most notably Personal Strain, Role Strain, and Relational/Interpersonal Demands. This comprehensive review examines the theoretical origins, psychometric properties, factor structure, scoring architecture, and clinical applications of the Caregiver’s Burden Scale.

2. Keywords

Caregiver Burden Scale, Zarit Burden Interview, informal caregiving, dementia care, psychological distress, role strain, personal strain, psychometrics, caregiver health, family gerontology

3. Authors

The Caregiver’s Burden Scale was developed by a pioneering research team at the Andrus Gerontology Center, University of Southern California (USC), under the leadership of:

• Steven H. Zarit, Ph.D.: Professor Emeritus of Human Development and Family Studies at The Pennsylvania State University and former faculty member at the University of Southern California. A prominent figure in clinical gerontology, Dr. Zarit’s scholarship focuses on interventions for family caregivers of individuals with dementia, mental health in late life, and family care dynamics.
• Karen E. Reever, M.S.W.: Clinical researcher and social gerontologist at the Ethel Percy Andrus Gerontology Center, University of Southern California, who specialized in clinical interventions and social support systems for spouses of cognitively impaired older adults.
• Julie Bach-Peterson, M.A.: Research associate and psychometrician at the University of Southern California, contributing extensively to the empirical conceptualization, item development, and field testing of the original Burden Scale.

4. Purpose

The primary purpose of the Caregiver’s Burden Scale is to provide a standardized, psychometrically rigorous self-report mechanism for assessing the magnitude of perceived stress, subjective appraisal of difficulty, and functional impairment experienced by family caregivers. During the late 1970s, clinical gerontology experienced a critical paradigm shift: institutionalization of older adults with progressive neurodegenerative conditions, such as Alzheimer’s disease, was increasingly recognized not merely as a medical necessity dictated solely by patient pathology, but rather as an outcome heavily mediated by the physical, emotional, and social depletion of the primary family caregiver. Prior to the establishment of the CBS, researchers lacked validated quantitative tools capable of distinguishing objective caregiving demands (e.g., hours of physical caregiving, functional activities of daily living) from subjective caregiver burden (the personal, internal psychological appraisal of those demands).

In clinical practice, the CBS serves several distinct functions:

• Screening and Risk Stratification: Identifying caregivers at elevated risk for burnout, clinical depression, somatic illness, and premature institutional placement of the care recipient.
• Treatment Planning: Pinpointing specific sources of caregiver strain—such as financial distress, personal isolation, boundary ambiguity, or guilt—to tailor psychoeducational, respite, and psychotherapeutic interventions.
• Outcome Assessment: Serving as a primary outcome measure in clinical trials evaluating the efficacy of pharmacological interventions for patients (e.g., cholinesterase inhibitors), community respite programs, cognitive-behavioral caregiver therapies, and support groups.
• Theoretical Modeling: Facilitating empirical research examining stress-coping dynamics, family resilience, and longitudinal adaptations to progressive chronic illnesses.

5. Psychological Construct

The core psychological construct measured by the Caregiver’s Burden Scale is subjective caregiver burden. In psychometric and gerontological literature, subjective burden is conceptualized as the state of physical, emotional, social, and economic exhaustion resulting from the perceived disparity between the unrelenting demands of the caregiving role and the personal resources, coping mechanisms, and external support systems available to the individual.

Subjective burden is distinctly multidimensional, encompassing several interconnected facets:

Personal Strain

Personal strain captures the direct psychological and internal emotional toll exerted upon the caregiver’s personal identity, self-efficacy, and physiological well-being. It reflects subjective feelings of exhaustion, anger, embarrassment over the patient’s behavioral disruptions, somatic depletion, and the perception of losing personal autonomy or control over one’s own life. For example, items measuring personal strain explore whether the caregiver feels angry around the relative or feels that their own health has suffered as a consequence of their caregiving involvement.

Role Strain

Role strain pertains to the external, structural friction between caregiving obligations and the individual’s competing developmental, social, and vocational roles. It reflects role overload, boundary impingements, restriction of social and recreational activities, loss of privacy, and friction with employment and other familial responsibilities. Typical indicators include feeling torn between caring for the relative and fulfilling obligations to other family members or employment, as well as an inability to invite friends into the home.

Relational and Dyadic Strain

This facet assesses the deterioration or reconfiguration of the dyadic relationship between the caregiver and the care recipient. It evaluates feelings of unreciprocated effort, manipulation, unrealistic dependency, unmet emotional expectations, and guilt over past interactions or current perceived deficits in care provision. Caregivers frequently experience ambiguous loss, wherein the physical presence of the care recipient is accompanied by profound psychological and cognitive absence.

Economic and Structural Strain

Economic burden captures the perceived inadequacy of material, medical, and financial resources required to sustain long-term home care while managing normal household liabilities. This dimension recognizes that financial strain frequently interacts synergistically with subjective psychological strain to exacerbate overall burden.

6. Theoretical Framework

The Caregiver’s Burden Scale is grounded conceptually in the Transactional Model of Stress and Coping formulated by Richard Lazarus and Susan Folkman (1984), alongside the Caregiver Stress Process Model later articulated by Leonard Pearlin and colleagues (1990).

According to Lazarus and Folkman’s transactional theory, psychological stress is not an inherent property of objective environmental stressors; rather, it emerges from a dynamic transaction between the individual and their environment. When confronted with the cognitive, functional, and behavioral decline of an impaired family member, the caregiver undertakes a primary appraisal, evaluating whether the situation presents a threat, harm, or challenge. This is followed by a secondary appraisal, wherein the caregiver evaluates the adequacy of their internal resources (e.g., emotional resilience, physical stamina) and external coping options (e.g., familial assistance, formal services, economic capital).

Zarit and colleagues applied this paradigm to family caregiving by demonstrating empirically that objective indicators of patient impairment (such as diagnostic severity or functional deficit scores) do not correlate linearly with caregiver institutionalization decisions or caregiver emotional breakdown. Instead, subjective appraisal—captured directly by the CBS items—serves as the critical mediating variable between objective patient impairment and caregiver adverse health outcomes. Pearlin’s Stress Process Model further contextualizes this by differentiating primary stressors (direct care demands, behavioral disturbances) from secondary role strains (family conflict, occupational disruption) and secondary intrapsychic strains (diminished self-esteem, mastery depletion, and internalized guilt). The CBS captures these secondary intrapsychic and relational strains, providing a standardized window into the caregiver’s phenomenological appraisal of their caregiving ecology.

7. Validity

The Caregiver’s Burden Scale and its derivative forms have undergone extensive psychometric validation across diverse clinical and cultural settings.

Construct and Convergent Validity

Convergent validity has been repeatedly established through significant positive correlations with validated measures of caregiver psychological distress. The CBS demonstrates moderate-to-strong positive correlations with the Center for Epidemiologic Studies Depression Scale (CES-D) (typically r = .50 to .68) and the Beck Depression Inventory (BDI) (r = .55 to .65). In a seminal validation study by Hébert, Bravo, and Préville (2000) involving informal caregivers of community-dwelling older adults with dementia, the French-Canadian adaptation of the 22-item CBS/ZBI demonstrated strong convergent correlations with caregiver psychological distress measured via the Ilfeld Psychiatric Symptom Index (r = .69) and inverse correlations with caregiver perceived health (r = -.45).

Discriminant Validity

Discriminant validity is supported by weak to non-significant correlations between CBS scores and objective measures of patient cognitive function, such as the Mini-Mental State Examination (MMSE) (correlations typically ranging from r = -.08 to -.21). This divergence reinforces the theoretical distinction between objective cognitive impairment in the patient and the subjective burden experienced by the family member.

Predictive and Criterion Validity

The CBS demonstrates robust predictive validity for longitudinal clinical endpoints. Higher baseline scores on the scale consistently predict subsequent caregiver clinical depression, heightened cardiovascular and neuroendocrine reactivity, caregiver medication use, and early institutionalization or nursing home placement of the care recipient. Longitudinal studies demonstrate that a persistent CBS score above clinical cutoff thresholds represents one of the strongest independent hazard predictors for terminating home care arrangements.

8. Reliability

The Caregiver’s Burden Scale exhibits exceptional reliability across various populations, languages, and caregiving contexts:

Internal Consistency

The internal consistency of the CBS has been extensively documented in gerontological literature:

• In the original and subsequent standardization cohorts, Cronbach’s alpha for the full item bank consistently exceeds .85, frequently falling between .87 and .93.
• Hébert et al. (2000) reported an overall Cronbach’s alpha of .92 for community caregivers, indicating high homogeneity of the scale items while maintaining broad domain coverage.
• Short forms (e.g., 12-item and 4-item screening variants) consistently maintain acceptable internal consistency coefficients ranging from .77 to .89.

Test-Retest Stability

Test-retest reliability assessments demonstrate that the CBS is a stable measure of persistent subjective burden over time, while remaining sensitive to genuine clinical interventions:

• Zarit et al. (1980) reported an initial test-retest correlation coefficient of .71 over a 4- to 6-week interval.
• Subsequent standardized retest studies over shorter intervals (1 to 2 weeks) have demonstrated intraclass correlation coefficients (ICC) ranging between .88 and .91, indicating minimal measurement error under stable caregiving conditions.

9. Factor Analysis

While the CBS was originally conceptualized as a unidimensional indicator of overall burden, decades of exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) have uncovered an underlying multidimensional architecture, though consensus on the exact number of subfactors varies depending on the population sampled.

Two-Factor Model (Personal Strain vs. Role Strain)

The most widely accepted and replicated structural model is the two-factor solution first systematically characterized by Whitlatch, Zarit, and von Eye (1991):

• Factor 1: Personal Strain: Characterized by high factor loadings (> .55) from items reflecting internal emotional distress, somatic fatigue, resentment, anger, and loss of control over one’s life (e.g., Items 5, 9, 10, 16, 17, 18). This factor reflects the direct psychological and physiological impact of caregiving.
• Factor 2: Role Strain: Dominated by items measuring structural conflicts between caregiving demands and external social, vocational, and personal life commitments, including lack of personal time, diminished privacy, and disrupted social relationships (e.g., Items 2, 3, 6, 11, 12, 13).

Alternative Factor Solutions

Other empirical investigations have identified three- to five-factor models:

• Three-Factor Model: Isolating (1) Impact on Caregiver’s Life, (2) Interpersonal Strain / Guilt, and (3) Expectations / Dependency.
• Five-Factor Model: Identified in specific cultural adaptations, disaggregating burden into Burden in Relationship, Emotional Well-Being, Social and Family Life, Finances, and Loss of Control.

Confirmatory factor analyses testing higher-order structures generally confirm that a second-order general burden factor accounts for the high inter-correlations among subfactors (CFI > .92, TLI > .90, RMSEA < .06), justifying both the interpretation of specific subscales and the computation of a composite burden score.

10. Instrument / Measurement Tool

• Instrument Name: Caregiver’s Burden Scale (CBS) / Zarit Burden Interview (ZBI)
• Developer(s): Steven H. Zarit, Karen E. Reever, and Julie Bach-Peterson (1980)
• Assessment Type: Standardized self-report rating scale (also administrable via structured clinical interview)
• Construct Measured: Subjective Caregiver Burden (Personal Strain, Role Strain, Dyadic/Relational Conflict, Economic Impingement)
• Item Count: 22 items in the standardized clinical version; 29 items in the extended historical and spouse-specific research item bank
• Response Scale: 5-point Likert-type frequency scale:
  • 0 = Never
  • 1 = Rarely
  • 2 = Sometimes
  • 3 = Quite frequently
  • 4 = Nearly always
• Scoring Method:
  • Items are scored from 0 to 4.
  • For the standard 22-item version, total composite scores range from 0 to 88, calculated by summing all completed items. Higher scores indicate greater subjective burden.
  • Standard Clinical Cutoff Benchmarks (22-item version):
    • 0 – 20: Little or no burden
    • 21 – 40: Mild to moderate burden
    • 41 – 60: Moderate to severe burden
    • 61 – 88: Severe burden
• Target Population: Adult family caregivers, particularly informal caregivers supporting individuals with Alzheimer’s disease, dementia, stroke, traumatic brain injury, cancer, or severe chronic mental illness.
• Administration Time: Approximately 5 to 10 minutes.

11. Permissions & Fee and Test Year

The Caregiver’s Burden Scale was first published in 1980 by Steven H. Zarit, Karen E. Reever, and Julie Bach-Peterson in The Gerontologist. The scale was developed under academic research auspices at the University of Southern California and has since become one of the most widely translated and utilized instruments in public-domain gerontological research.

Researchers and clinicians should note that while the original 1980 scale items were published in peer-reviewed literature, the commercial distribution and copyrighted multi-language licensing of specific standardized variants (notably later copyrighted editions distributed through Mapi Research Trust / PROQOLID) are managed under formal institutional agreements. For non-funded, non-commercial clinical practice and independent academic research, the scale is broadly accessible through standard scientific publications and clinical assessment repositories. Commercial clinical trials and sponsored pharmaceutical research typically require licensing clearance and translation certifications from the copyright administrators.

12. References

• Deeken, J. F., Taylor, K. L., Mangan, P., Yabroff, K. R., & Ingham, J. M. (2003). Care for the caregivers: A review of self-report instruments developed to measure the burden, needs, and quality of life of informal caregivers. Journal of Pain and Symptom Management, 26(4), 922–953. https://doi.org/10.1016/S0885-3924(03)00327-0
• Hébert, R., Bravo, G., & Préville, M. (2000). Reliability, validity, and reference values of the Zarit Burden Interview for assessing informal caregivers of community-dwelling older persons with dementia. Canadian Journal on Aging / La Revue canadienne du vieillissement, 19(4), 494–507. https://doi.org/10.1017/S0714980800012484
• Lazarus, R. S., & Folkman, S. (1984). Stress, appraisal, and coping. Springer Publishing Company.
• Pearlin, L. I., Mullan, J. T., Semple, S. J., & Skaff, M. M. (1990). Caregiving and the stress process: An overview of concepts and their measures. The Gerontologist, 30(5), 583–594. https://doi.org/10.1093/geront/30.5.583
• 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.
• Whitlatch, C. J., Zarit, S. H., & von Eye, A. (1991). Efficacy of interventions with caregivers: A reanalysis. The Gerontologist, 31(1), 9–14. https://doi.org/10.1093/geront/31.1.9
• Zarit, S. H., Reever, K. E., & Bach-Peterson, J. (1980). Relatives of the impaired elderly: Correlates of feelings of burden. The Gerontologist, 20(6), 649–655. https://doi.org/10.1093/geront/20.6.649

13. Items of the Scale