Health Assessment Questionnaire Disability Index (HAD-QI)

Original Editor - Kapil Narale

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Introduction[edit | edit source]

The Health Assessment Questionnaire - Disability Index (HAQ-DI) measures health related quality of life factors in various parts of an illness or injury process. It was initially adopted for the use in the assessment of arthritis, but can be used to assess any type of condition. It was designed to measured patient centered and patient assessed outcomes, and can be useful in conditions or life stages such as normal ageing, therapy of rheumatoid arthritis, developing risk factor models of osteoarthritis, and examination of mortality risk in rheumatoid arthritis. [1] It is a self-assessment tool used to measure functional ability in eight different areas: rising, dressing and grooming, hygiene, eating, walking, reach, grip, and activities of independent living. [2]

The HAQ-DI addresses general patient centered outcomes. [1] It has been administered by the Stanford Arthritis, Rheumatism, and Aging Medical Information System (ARAMIS) many times to assess clinical status, deem the effectiveness in clinical and observational trials, and outline health qualifiers. It has been adopted by the American College of Rheumatology for measuring physical function in rheumatoid arthritis studies. [1]

Development of the HAQ[edit | edit source]

The HAQ-DI was developed at Stanford University. It was developed in 1978 by James F. Fries, MD, and Colleagues. The primary HAQ scale was developed at the Stanford Arthritis Center, and acknowledges the American Rheumatism Association functional class measure. [1]

The components of the 2-page HAQ-DI have remained the same since near the time of developed, while the full HAQ-DI has been periodically updated with more relevant questions overtime. [1]

What is the HAQ-DI & Why use it?[edit | edit source]

The HAQ-DI is a quantitative tool used to assess health related quality of life assessments related to many types of injuries or illnesses. Since it was adopted through rheumatology, it can be known to only classify diseases, but as mentioned it is used across various conditions. Instead of being classified as 'disease specific', it should be classified as 'generic', since it it assesses the dimensions of death, disability, drug side effects, discomfort, and economic costs. [1]

Measuring or assessing Health related quality of life is important at any stage of any condition or or injury. A valid and reliable tool, which can measure and assess over long periods greater than 6 weeks is needed for such a measurement, and thus the HAQ-DI plays an important role. [1]

As mentioned, the HAQ-DI can be used in the assessment of functional ability in a multitude number of activities or conditions. It was used in a study exploring long distance running or vigorous activity and the incidence of knee osteoarthritis. [3]

What it Measures[edit | edit source]

The full version of the HAQ collects information of five patient-centered categories, to: [1]

  • Avoid Disability
  • Be free of Pain and Discomfort
  • Avoid adverse Treatment Effects
  • Keep dollar costs of treatments low
  • Prevent the likelihood of Death


The questionnaire also includes sections on drug side effects, medical costs, and other sections on demographics, lifestyle, and health behaviors. [1]

The most commonly used version is the HAQ, which is the 'short' or 2-page version. This version includes the HAQ Disability Index (HAQ-DI), the HAQ Visual Analog Scale (VAS) for pain, and the VAS patient global health scale. [1]

The disability assessment component of the HAQ, making it the HAQ-DI, measures the patient's capacity for functional tasks. [1] This collects information on fine motor skills of the upper limb, locomotion of the lower limb, and activities that jointly involve movement of the upper and lower limbs. [1]

There are 20 questions which span eight categories, and account for different functional activities. [1] These eight categories include rising, dressing and grooming, hygiene, eating, walking, reach, grip, and activities of independent living. [1][2] These items are asked in terms of a span over the previous week. The patient responds on a scale of 0 (no disability) to 3 (completely disabled). There are at least two questions from each category. [1]

HAQ VAS Pain Scale[edit | edit source]

This scale was developed to assess the presence and severity of arthritis related pain. The intention is to gather information from the patient on their experience of the pain over the previous week, although this pain may vary between days. There are two VAS scales which are scored from 0 (no pain) to 3 (intense pain) or 0 (no pain) to 100 (intense pain). This is generally used in experimental, observational, and clinical settings.[1]

Other Dimensions of the full HAQ[edit | edit source]

The full HAQ also collects information on Drug Toxicity. Such information includes the name or type of drug, dosage and frequency taken, period of time drug was in use, specific side effects experienced, degree of severity of these side effects, the importance of the drug to the patient, and drug course as a result of any side effects. [1]

There is also a section called summary Toxicity Index which categorises the severity of toxicity from various medications. Information relating to costs is also included in the full HAQ. Death, and mortality related information are also included in the HAQ. [1]

There is also a VAS scale used in both the 2-page HAQ tool and the full HAQ, It is used to measure quality of life. It is scored from 0 (very well) to 100 (very poor). [1]

Scoring[edit | edit source]

The HAQ-DI is sensitive to change. It helps estimate future disability and costs. The scoring of the scale has been adapted from the American Rheumatism Association/American College of Rheumatology functional classes. [1]

Each item or question is rated on a scale of 0 to 3, with 0 (normal/no difficulty), 1 (some difficulty), 2 (much difficulty), and 3 (unable to do). The highest component score within each category represents the score for that category, but not with the use of aids or other devices to complete the tasks. With the use of equipment or aids, a lower score is raised to 2, to reflect the underlying disabilities. [1]

The 8 category scores are averaged, which represent an overall score from 0 (no disability) to 3 (completely disabled). If the questionnaire is slightly changed to reflect a certain disease, this does not affect the respective scoring. [1]

This measurement of disability helps indicate mortality rates, rates of aging, and the usage of healthcare resources. [1]

This scoring helps measure the intensity of arthritis related pain. [1]

Interpretation of Scoring[edit | edit source]

Scores 0-1 indicates mild to moderate disability, 1-2 indicates moderate to severe disability, and 2-3 indicates severe to very severe disability. [1]

Statistical Significance[edit | edit source]

The HAQ-DI has been shown to have face and content validity compared to other measurement tools for differing diseases. Construct validity, predictive validity, and sensitivity to change have been proven in many studies and clinical trials. There is also proven convergent validity based on correlations with various clinical and laboratory assessments. The validity of the HAQ pain scale and global health status scale are also strong. [1]

The HAQ-DI is quite responsive to change, and is very sensitive to change when compared to other health assessment outcome measures. [1]

Limitations[edit | edit source]

There are a few limitations noted in regards to the HAQ-DI.

It does not account for non-visible disabilities such as sensory organ dysfunctions, and psychiatric dysfunctions. It also does not collect information about patient or personal satisfaction and social activity. [1]

Resources[edit | edit source]

Here is a link to a document explaining the instructions to the HAQ-DI.

Here is a link to the 2-page HAQ-DI from the British Columbia Ministry of Health.

Here is a 2-page 20-item Disability Scale from the Stanford Patient Education Research Center

References[edit | edit source]

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 1.16 1.17 1.18 1.19 1.20 1.21 1.22 1.23 1.24 1.25 1.26 1.27 Bruce Bonny, Fries J. F. The Stanford Health Assessment Questionnaire: Dimensions and Practical Applications. Health and Quality of Life Outcomes. 2003:1:20:1-6.
  2. 2.0 2.1 Chakravarty E. F, Hubert H. B, Lingala V. B, Zatarain E, Fries J. F. Long Distance Running and Knee Osteoarthritis A Prospective Study. 2008:35(2):133-138.
  3. Chakravarty E. F, Hubert H. B, Lingala V. B, Zatarain E, Fries J. F. Long Distance Running and Knee Osteoarthritis A Prospective Study. 2008:35(2):133-138.