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Home›Health Measurement›HAQ Disability Index
Process / pipelineFunctional assessment

HAQ Disability Index

Health Assessment Questionnaire Disability Index · Also known as: HAQ-DI, Health Assessment Questionnaire, Disability Index

The Health Assessment Questionnaire Disability Index (HAQ-DI) is a 20-item self-report measure of functional disability developed by Fries and colleagues at Stanford University in 1980. Originally designed for rheumatoid arthritis, the HAQ-DI has become the gold-standard functional assessment instrument across diverse rheumatic diseases and chronic conditions.

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HAQ Disability Index
Duke Health ProfileEQ-5DMOS Social Support SurveySF-36 Health SurveyWHOQOL-BREFInternational Physical A…Sickness Impact Profile

When to use it

The HAQ-DI is the preferred instrument for assessing functional outcomes in rheumatic disease trials and clinical practice monitoring. It is appropriate for patients aged 5+ years across all arthropathies (rheumatoid arthritis, systemic lupus erythematosus, osteoarthritis, etc.). The HAQ-DI is less suitable for acute injury or post-surgical assessment; condition-specific functional scales may be preferable in those contexts.

Strengths & limitations

Strengths
  • Extensively validated across rheumatic diseases with strong correlation to other functional and clinical measures
  • Sensitive to change in clinical trials; detects meaningful functional improvement and decline
  • Simple, intuitive scoring reflects practical disability relevant to patients' lived experience
  • Brief administration time (5 minutes) and self-completion enable use in busy clinical settings
  • Strong predictive validity for health outcomes, joint damage progression, and mortality in arthritis
Limitations
  • Originally designed for arthritis; extrapolation to non-rheumatic conditions may require validation
  • Predominantly assesses physical function; does not capture cognitive or emotional disability
  • Ceiling effects in mild disease; limited discrimination among high-functioning patients
  • Assistive device/help factors may not apply uniformly across cultural contexts and healthcare systems

Frequently asked

What is the significance of the assistive device and help factors in HAQ-DI scoring?

The use of assistive devices or needing help from another person reflects disease severity beyond difficulty rating alone. A patient unable to climb stairs even with a cane (score 3 with device) has greater functional impairment than one with difficulty but independence. This weighting makes HAQ-DI more sensitive to real-world disability.

What does a HAQ-DI score of 0.75 indicate?

A score of 0.75 indicates moderate to moderately severe disability, suggesting the patient has significant limitations in routine activities. Contextually, this reflects meaningful disease burden; improvement to 0.5 or below would represent clinically important response to treatment in arthritis trials.

Can HAQ-DI be used in conditions other than rheumatoid arthritis?

The HAQ-DI has been used in systemic lupus erythematosus, osteoarthritis, and other conditions with varying degrees of validation. When using it outside arthritis, ensure the conceptual basis (physical functional limitation) aligns with your condition and validate thresholds against relevant outcome measures.

How often should HAQ-DI be assessed in clinical monitoring?

In clinical practice, HAQ-DI is typically assessed at baseline and at defined follow-up intervals (e.g., quarterly or semi-annually) aligned with disease activity monitoring. In trials, assessment frequency depends on expected rate of functional change; monthly in intensive interventions, quarterly in typical drug trials.

Sources

  1. Bruce, B., & Fries, J. F. (1989). The Stanford Health Assessment Questionnaire: a review of its history, issues, progress, and documentation. Journal of Rheumatology, 16(8), 1055–1064. link ↗
  2. Fries, J. F., Spitz, P., Kraines, R. G., & Holman, H. R. (1980). Measurement of patient outcome in arthritis. Arthritis & Rheumatism, 23(2), 137–145. DOI: 10.1002/art.1780230202 ↗
  3. Pincus, T., Swearingen, C., & Wolfe, F. (2011). Toward a multidimensional Health Assessment Questionnaire (MDHAQ): assessment of advanced activities of daily living and psychological well-being. Seminars in Arthritis and Rheumatism, 30(2), 10–17. link ↗

How to cite this page

ScholarGate. (2026, June 3). Health Assessment Questionnaire Disability Index. ScholarGate. https://scholargate.app/en/health-measurement/haq-disability-index

Related methods

Duke Health ProfileEQ-5DMOS Social Support SurveySF-36 Health SurveyWHOQOL-BREF

Which method?

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  • Duke Health ProfileHealth Measurement↔ compare
  • EQ-5DHealth Measurement↔ compare
  • MOS Social Support SurveyHealth Measurement↔ compare
  • SF-36 Health SurveyHealth Measurement↔ compare
  • WHOQOL-BREFHealth Measurement↔ compare
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Referenced by

EQ-5DInternational Physical Activity QuestionnaireMOS Social Support SurveySickness Impact Profile

Similar methods

RA-QoLRoutine Assessment of Patient Index Data 3WOMAC Osteoarthritis IndexDisease Activity Score 28Hip Disability and Osteoarthritis Outcome ScoreSF-36 Health SurveyPsoriatic Arthritis Quality of Life ScaleBath Ankylosing Spondylitis Functional Index

Related reference concepts

Functional Assessment and Disability MeasuresRheumatoid ArthritisFunctional Assessment and DisabilityPatient-Reported Outcome MeasuresEarly Arthritis Assessment and ManagementMusculoskeletal Disorders and Arthritis

Spotted an issue on this page? Report or suggest a fix →

ScholarGate — HAQ Disability Index (Health Assessment Questionnaire Disability Index). Retrieved 2026-07-21 from https://scholargate.app/en/health-measurement/haq-disability-index · Dataset: https://doi.org/10.5281/zenodo.20539026
Quick facts
Originator
James Fries and colleagues at Stanford University
Subfamily
Functional assessment
Year
1980
Type
Functional disability measurement for arthritis and chronic disease
Related methods
Duke Health ProfileEQ-5DMOS Social Support SurveySF-36 Health SurveyWHOQOL-BREF
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