The Hip Disability and Osteoarthritis Outcome Score, or HOOS, is a 40-item patient-reported outcome measure used to assess hip pain, symptoms, daily function, sport and recreation function, and hip-related quality of life. It can support monitoring and progress tracking for hip osteoarthritis, hip disability and post-operative hip recovery, but it does not diagnose a condition or determine return-to-activity readiness on its own.

Introduction

Hip problems can affect walking, stairs, sitting, standing, squatting, running, sport, work tasks, sleep, confidence and quality of life.

The Hip Disability and Osteoarthritis Outcome Score, commonly called the HOOS, is a hip-specific patient-reported outcome measure designed to capture the client’s own view of their hip symptoms, function and quality of life.

It is commonly used for:

• hip osteoarthritis
• hip disability monitoring
• total hip replacement or total hip arthroplasty follow-up
• hip pain progress tracking
• post-operative hip recovery
• daily function monitoring
• sport and recreation limitations
• long-term outcome reporting

The HOOS includes five separately scored subscales: Pain, Symptoms, Activities of Daily Living, Sport and Recreation, and Hip-Related Quality of Life. Scores are transformed to a 0–100 scale, where 100 represents no hip problems and 0 represents extreme hip problems.  

Quick Summary

• Outcome measure: Hip Disability and Osteoarthritis Outcome Score
• Abbreviation: HOOS
• Body region: Hip
• Type: Patient-reported outcome measure
• Number of items: 40
• Subscales: Pain, Symptoms, Activities of Daily Living, Sport/Recreation, Quality of Life
• Score range: 0–100 for each subscale
• Higher score means: Better perceived hip status
• Lower score means: More pain, symptoms, limitation or quality-of-life impact
• Related versions: HOOS-12, HOOS-PS, HOOS-JR
• Best used for: Baseline assessment, reassessment, progress tracking and outcome reporting
• Key limitation: HOOS does not diagnose a condition or determine clearance on its own

What Is the Hip Disability and Osteoarthritis Outcome Score?

The HOOS is a hip-specific patient-reported outcome measure.

It was developed to assess symptoms and functional limitations in people with hip disability and hip osteoarthritis. The original HOOS validation study evaluated its validity and responsiveness in people with primary hip osteoarthritis assigned for total hip replacement.  

The five HOOS subscales are:

• Pain
• Other Symptoms
• Activities of Daily Living
• Sport and Recreation Function
• Hip-Related Quality of Life

The HOOS includes all WOMAC questions in unchanged form, with additional items designed to capture hip-related problems beyond basic osteoarthritis symptoms.  

Why It Is Used

The HOOS is used because physical tests alone do not always explain how a hip problem affects a client’s daily life, activity participation or quality of life.

A client may show improving strength or range of motion but still report:

• pain with stairs
• difficulty walking longer distances
• trouble getting in and out of chairs or cars
• stiffness after sitting
• reduced sport or recreation participation
• difficulty with socks, shoes or dressing
• reduced confidence with movement
• frustration with persistent symptoms

The HOOS can help professionals:

• establish a baseline
• identify which domains are most affected
• monitor change over time
• support client education
• guide goal-setting conversations
• compare symptoms and function across reassessments
• combine client-reported outcomes with physical testing
• improve reporting quality in Measurz

The HOOS should support assessment reasoning and progress tracking. It should not be used as a stand-alone diagnostic, treatment or clearance tool.

What It Measures

Pain

The Pain subscale captures hip pain during different activities and situations.

It may provide insight into pain during:

• walking
• stairs
• standing
• sitting
• bending
• twisting or pivoting
• night-time or rest

Symptoms

The Symptoms subscale captures other hip-related symptoms.

This may include:

• stiffness
• restricted movement
• grinding or clicking
• symptom severity
• movement-related discomfort

Activities of Daily Living

The ADL subscale captures day-to-day functional ability.

This may include:

• walking
• stairs
• standing
• sitting
• getting in and out of a car
• rising from sitting
• putting on socks or shoes
• household tasks

Sport and Recreation

The Sport/Recreation subscale captures higher-demand activity.

This may include:

• squatting
• running
• twisting
• pivoting
• recreational activity
• sport participation

Hip-Related Quality of Life

The Quality of Life subscale captures the broader impact of the hip problem.

This may include:

• confidence
• lifestyle impact
• awareness of the hip
• frustration
• participation restriction
• concerns about the future

Who It Is Useful For

The HOOS may be useful for:

• exercise professionals
• rehabilitation practitioners
• strength and conditioning coaches
• allied health support teams
• movement assessment professionals
• students learning outcome measures
• professionals using Measurz or MAT for structured progress tracking

It may be relevant for clients with:

• hip osteoarthritis
• hip disability
• hip pain
• post-operative hip recovery
• total hip replacement follow-up
• reduced walking or stair tolerance
• hip-related sport or recreation limitations
• persistent stiffness, pain or quality-of-life impact

When to Use This Outcome Measure

Use the HOOS when you want to understand how a hip problem affects the client’s pain, symptoms, function and quality of life.

It may be useful at:

• initial assessment
• onboarding
• reassessment
• hip osteoarthritis monitoring
• post-operative milestones
• pre- and post-total hip replacement monitoring
• return-to-walking or return-to-activity planning
• discharge or progress review

The HOOS is most useful when repeated over time using the same version and scoring method.

When Not to Use or When to Be Cautious

Use caution when:

• the client cannot complete the questionnaire independently
• literacy, language or cognitive factors affect responses
• the wrong language version is being used
• multiple body regions are contributing to limitation
• the client has not attempted the activities being scored
• many items are missing
• the score is being used as a pass/fail decision
• the result is interpreted without physical assessment context

The HOOS should not be used to:

• diagnose hip osteoarthritis
• confirm structural hip pathology
• determine tissue healing
• identify the exact cause of symptoms
• clear someone for sport or activity
• replace professional judgement
• replace medical assessment when needed

Equipment or Resources Required

• HOOS questionnaire
• Official scoring guide or validated calculator
• Measurz recording workflow
• Client-reported symptom and function notes
• Baseline and retest dates
• Optional related physical tests, such as:
  • hip range of motion
  • hip strength testing
  • gait assessment
  • sit-to-stand testing
  • step or stair assessment
  • single-leg balance
  • single-leg squat
  • walking tolerance
  • pain with key movements

Administration Protocol / Practice

Setup

Explain the purpose of the questionnaire before the client completes it.

Example wording:

“This questionnaire helps us understand how your hip is affecting your pain, symptoms, daily function, sport and quality of life. It does not diagnose the problem on its own, but it helps us monitor change over time.”

Format

The HOOS can be completed:

• on paper
• digitally
• independently
• with assistance
• before a session
• during reassessment
• as part of a Measurz workflow

Client Instructions

Ask the client to:

• answer based on their current hip problem
• choose the response that best matches their experience
• answer every item where possible
• avoid overthinking each question
• ask for clarification if they do not understand the wording
• complete the same version at each retest

Completion Method

Record whether the HOOS was completed:

• independently
• digitally
• on paper
• verbally
• with assistance

This matters because assistance, wording clarification or completion format may influence responses.

Assistance Rules

If help is required:

• explain the instructions without leading the answer
• avoid telling the client which response to choose
• record that assistance was provided
• use the same assistance approach at retest where possible

Missing Item Handling

Do not guess missing responses.

Use the official scoring guidance for the version being used. If too many items are missing for a subscale, record that subscale as incomplete rather than creating an unreliable score.

Scoring Process

Each HOOS item is scored from 0 to 4.

Each subscale is transformed to a 0–100 score.

General scoring direction:

• 100: no hip problems
• 0: extreme hip problems

The five subscales should be interpreted separately rather than combined into one unsupported total score.

Retesting Considerations

Retest at meaningful time points, such as:

• baseline
• after a training block
• after a rehabilitation phase
• after a flare-up
• pre-surgery or post-surgery milestone
• post-operative review
• discharge or progress review

For consistency, record:

• date
• current activity level
• recent flare-ups
• recent training load
• walking exposure
• stair exposure
• whether the client has returned to activities being scored
• any major changes in work, sport or daily demands

Safety Notes

The HOOS is a self-report questionnaire, so it does not create physical testing risk.

However, a major worsening in score may support further assessment if the client reports:

• severe deterioration
• major quality-of-life impact
• worsening function
• severe pain
• unexpected decline
• new or changing symptoms

Scoring and Interpretation

The HOOS has five separate subscale scores.

Each subscale ranges from 0 to 100.

Higher scores indicate better perceived hip status.

Lower scores indicate more reported problems.

Subscales

• Pain: 0–100
• Symptoms: 0–100
• Activities of Daily Living: 0–100
• Sport/Recreation: 0–100
• Quality of Life: 0–100

What a High Score May Suggest

A higher score may suggest:

• less hip pain
• fewer hip symptoms
• better daily function
• better sport or recreation function
• better hip-related quality of life
• improved confidence with hip-related activity

What a Low Score May Suggest

A lower score may suggest:

• more pain
• more symptoms
• reduced daily function
• reduced sport or recreation capacity
• reduced confidence
• greater hip-related quality-of-life impact

What the Score Does Not Prove

A HOOS score does not prove:

• the diagnosis
• the tissue source of symptoms
• the severity of structural change
• readiness to return to sport or activity
• whether imaging is required
• whether a specific intervention caused the change

How to Explain the Result Safely

Example wording:

“Your HOOS results suggest your daily function is improving, but your pain and quality-of-life scores are still affected. This does not tell us exactly what structure is causing symptoms, but it helps us understand how your hip is affecting the activities that matter to you.”

What the Score May Mean in Different Client Populations

General Fitness Clients

For general fitness clients, HOOS can help show how hip symptoms affect:

• walking
• stairs
• sitting
• standing
• gym training
• recreational exercise
• daily activity

Interpretation cautions:

• scores may change with recent activity
• symptoms from the low back, knee or pelvis may affect answers
• sport items may be less relevant if the client does not participate in sport

Sport and Performance Clients

For sport and performance clients, Sport/Recreation and Quality of Life may be especially important.

A client may report limitations with:

• running
• squatting
• twisting
• pivoting
• gym training
• change of direction
• confidence with sport-specific movement

Interpretation should include sport-specific testing. A high HOOS score should not be treated as clearance on its own.

Older Adults

For older adults and people with hip osteoarthritis, HOOS may help monitor:

• pain
• stiffness
• walking tolerance
• stair tolerance
• quality of life
• daily function

Interpretation cautions:

• other health conditions may affect scores
• general strength and balance may influence function
• walking exposure and activity level should be recorded
• broad reference values should be used cautiously

Youth Clients

Standard HOOS is not primarily designed as a youth measure.

For youth clients, consider:

• reading level
• comprehension
• parent or guardian assistance
• sport exposure
• whether a youth-specific or hip-specific measure may be more appropriate

If assistance is provided, record it clearly.

Clients With Hip Osteoarthritis

HOOS is especially relevant for hip osteoarthritis because it was developed and validated for hip disability and osteoarthritis contexts.

Interpretation should consider:

• flare-ups
• medication changes
• activity exposure
• walking tolerance
• stair function
• strength and range of motion
• quality-of-life impact

Clients After Total Hip Replacement

For total hip replacement or total hip arthroplasty, HOOS can help track changes before and after surgery.

Interpretation should consider:

• surgery date
• post-operative stage
• restrictions
• walking exposure
• pain medication
• expected recovery timeline
• medical or surgical guidance where relevant

The original validation study found the HOOS met validity and responsiveness criteria in people with primary hip osteoarthritis assigned for total hip replacement.  

Clients With Persistent Symptoms

For persistent hip symptoms, HOOS can help monitor broader impact beyond pain.

Scores may be influenced by:

• confidence
• activity avoidance
• expectations
• flare-up patterns
• participation restrictions
• quality-of-life impact

Meaningful Change, MCID, MDC and Responsiveness

Meaningful change values help interpret whether a score change is likely to matter.

Key terms:

• MCID / MIC: the smallest change that may be meaningful to clients or professionals, depending on the method used
• MDC: the amount of change likely needed to exceed measurement error
• SEM: the estimated measurement error around a score
• Responsiveness: the ability of the measure to detect change over time
• PASS: patient acceptable symptom state
• SCB: substantial clinical benefit

HOOS Meaningful Change Evidence

Meaningful change values for HOOS vary depending on the population, HOOS version, subscale and clinical context.

A 2024 systematic review examined MCID, MIC, CID, MDC and PASS values for commonly used PROMs after total hip arthroplasty. This is relevant for THA settings but should not be applied automatically to non-surgical hip pain or sport populations.  

Recent work has also examined short-term MCID values for HOOS after total hip arthroplasty at 3 and 6 months, using an anchor-based approach. Those values are specific to the study’s THA population and timeframe.  

Practical Interpretation

When interpreting HOOS change:

• compare each subscale to baseline
• use population-specific MCID, MIC, MDC or SEM where available
• avoid applying one universal threshold to every hip presentation
• look for consistent improvement across relevant subscales
• compare score change with client goals
• check whether activity exposure has increased
• consider pain, strength, range of motion and functional tests

When Values Are Uncertain

Reported meaningful change values may vary by:

• condition
• age
• surgery type
• non-surgical versus surgical care
• subscale
• language version
• follow-up timeframe
• anchor method
• baseline severity

When no matching value exists, interpretation should rely more heavily on:

• baseline comparison
• repeated measurement
• client-reported change
• physical assessment findings
• activity exposure
• professional judgement

Normative Data, Reference Values or Comparative Data

Published HOOS reference values are available, but they should be applied carefully.

A 2023 Danish population-based study established reference values for the five HOOS subscales and HOOS-12 using a representative sample of Danish citizens aged 18 years and older. The study noted that reference data can improve interpretation of HOOS and HOOS-12 scores.  

Earlier population-based reference work also reported that hip complaints differ across age and sex, supporting the need to interpret HOOS scores with demographic context rather than as one universal cut-off.  

Reference values provide context, but interpretation should consider whether the reference population matches the client’s:

• age
• sex
• country
• health status
• hip osteoarthritis status
• BMI
• activity level
• sport or work demands
• surgical history

Practical guidance:

• Scores closer to 100 generally suggest fewer reported hip problems.
• Lower scores suggest greater pain, symptoms, functional limitation or quality-of-life impact.
• Sport/Recreation and Quality of Life may remain limited after ADL improves.
• Population reference values provide context, not strict pass/fail thresholds.
• The client’s own baseline is often the most useful comparison.

Reliability and Validity

The HOOS has post-2000 evidence supporting its use across hip osteoarthritis and total hip replacement contexts.

The original HOOS validation study evaluated people with primary hip osteoarthritis assigned for total hip replacement and found that HOOS met criteria for validity and responsiveness.  

A large validation study of HOOS and KOOS pain and function subscales in total hip and total knee replacement found evidence supporting construct validity for HOOS/KOOS pain and ADL function measures in these surgical populations.  

More recent research has examined HOOS psychometrics in large registry data after total hip arthroplasty, reflecting ongoing interest in structural validity and measurement quality for HOOS and related versions.  

Reliability and validity are stronger when:

• the correct HOOS version is used
• the same scoring method is repeated
• all relevant items are completed
• subscales are interpreted separately
• the correct language version is used
• retesting occurs at meaningful time points
• results are interpreted alongside physical and functional assessment

Interpret cautiously when:

• many items are missing
• the client has not attempted sport or work tasks yet
• only one subscale changes slightly
• the change is smaller than known measurement error or meaningful change
• symptoms are strongly influenced by a recent flare-up
• the score is being used without objective assessment context

Common Errors and Limitations

Common errors include:

• treating HOOS as a diagnosis
• using HOOS as return-to-sport or return-to-activity clearance
• combining subscales into one unsupported total score
• ignoring missing items
• using inconsistent scoring methods
• not recording the version used
• not recording the completion date
• comparing scores without considering activity exposure
• over-interpreting small changes
• using reference values as strict pass/fail cut-offs

Limitations include:

• self-report can be influenced by mood, expectations and recent activity
• sport items may be less meaningful if the client has not returned to sport
• scores do not identify the exact physical cause of symptoms
• meaningful change values vary by condition and population
• reference values may not match the client’s age, activity level or condition
• HOOS should be paired with physical tests and client goals

Practical Applications

The HOOS may help professionals:

• document baseline hip status
• identify whether pain, symptoms, daily function, sport or quality of life are most affected
• track change over time
• monitor hip osteoarthritis symptoms
• monitor post-operative hip recovery
• support goal setting
• improve client education
• communicate progress with a broader team
• strengthen Measurz reports

For older adults or people with hip osteoarthritis, HOOS can help monitor walking, stairs, stiffness, pain and quality-of-life impact.

For post-surgical clients, HOOS can help track self-reported progress after total hip replacement when interpreted with recovery stage and professional guidance.

For active clients, HOOS can highlight whether sport and recreation remain limited despite improvements in daily function.

For Measurz users, HOOS is most useful when combined with objective measures such as:

• hip range of motion
• hip strength
• walking tolerance
• sit-to-stand testing
• stair assessment
• single-leg balance
• gait assessment
• pain with key movements

How to Record This in Measurz

Record:

• outcome measure name: Hip Disability and Osteoarthritis Outcome Score / HOOS
• version used: HOOS, HOOS-12, HOOS-PS, HOOS-JR or other
• date completed
• completion method: paper, digital, interview or assisted
• language/version used
• condition or presentation being tracked
• side involved: left, right or bilateral
• Pain subscale score
• Symptoms subscale score
• ADL subscale score
• Sport/Recreation subscale score
• Quality of Life subscale score
• score range: 0–100
• direction of scoring: higher score indicates better status
• missing items, if any
• assistance provided, if any
• current pain score, if relevant
• current symptoms
• current activity or sport exposure
• walking or stair exposure
• key functional limitations
• confidence or participation goals
• baseline comparison
• MCID/MDC/MIC/PASS comparison where supported
• related physical assessment findings
• interpretation notes
• retest date
• referral or further assessment notes where appropriate

Record whether the main limitation appears to be:

• pain dominant
• symptom or stiffness dominant
• daily function limitation
• sport/recreation limitation
• quality-of-life limitation
• mixed presentation
• unclear due to incomplete responses

This improves:

• repeatability
• communication
• client education
• assessment reasoning
• monitoring over time
• team consistency
• reporting quality

Related Outcome Measures / Internal Links

• Copenhagen Hip and Groin Outcome Score / HAGOS
• Lower Extremity Functional Scale / LEFS
• Knee Injury and Osteoarthritis Outcome Score / KOOS
• Lysholm Knee Scoring Scale
• Foot and Ankle Outcome Score / FAOS
• Foot & Ankle Disability Index / FADI
• Pain Self-Efficacy Questionnaire / PSEQ
• Tampa Scale for Kinesiophobia / TSK
• Fear-Avoidance Beliefs Questionnaire / FABQ

FAQs

What does the HOOS measure?

The HOOS measures self-reported hip pain, symptoms, daily function, sport and recreation function, and hip-related quality of life.

How many items are in the HOOS?

The full HOOS has 40 items across five subscales.

How is the HOOS scored?

Each subscale is converted to a 0–100 score. A higher score indicates better perceived hip status.

Is there one total HOOS score?

HOOS is usually interpreted using five separate subscale scores rather than one combined total score.

Does HOOS diagnose hip osteoarthritis?

No. HOOS does not diagnose hip osteoarthritis or any other hip condition. It measures the client’s perceived symptoms, function and quality-of-life impact.

What is a meaningful change in HOOS?

Meaningful change depends on the population, condition, subscale and HOOS version. Use MCID, MIC, MDC, SEM or PASS values only when they match the client group and context.

Can HOOS be used after total hip replacement?

Yes. HOOS is commonly used in total hip replacement and total hip arthroplasty contexts, but results should be interpreted with recovery stage, medical guidance and physical findings.

Can HOOS be used for return-to-sport decisions?

HOOS can support return-to-activity reasoning, especially the Sport/Recreation and Quality of Life subscales, but it should not be the only clearance measure.

Key Takeaways

• HOOS is a 40-item hip-specific patient-reported outcome measure.
• It includes Pain, Symptoms, ADL, Sport/Recreation and Quality of Life subscales.
• Each subscale is scored from 0 to 100.
• Higher scores indicate better perceived hip status.
• HOOS does not diagnose hip osteoarthritis or clear a client for sport or activity.
• Meaningful change values should be matched to the population, subscale and context.
• Published reference values are available, but they should be used as context rather than strict pass/fail standards.
• Measurz should record each subscale, version, completion method, side, baseline comparison, related findings and retest plan.

References

Braaksma, C., Leclercq, W. K. G., Tordoir, R. L., et al. (2020). Systematic review and meta-analysis of measurement properties of the Hip disability and Osteoarthritis Outcome Score - Physical function Shortform (HOOS-PS) and the Knee Injury and Osteoarthritis Outcome Score - Physical function Shortform (KOOS-PS). Osteoarthritis and Cartilage, 28(12), 1525–1538. https://doi.org/10.1016/j.joca.2020.09.005

Larsen, P., et al. (2023). National population-based reference data for the Hip Disability and Osteoarthritis Outcome Score (HOOS). Archives of Orthopaedic and Trauma Surgery. https://doi.org/10.1007/s00402-023-04915-w

Nilsdotter, A. K., Lohmander, L. S., Klässbo, M., & Roos, E. M. (2003). Hip disability and Osteoarthritis Outcome Score (HOOS): Validity and responsiveness in total hip replacement. BMC Musculoskeletal Disorders, 4, 10. https://doi.org/10.1186/1471-2474-4-10

Sundén, A., Lidengren, K., Roos, E. M., Lohmander, L. S., & Ekvall Hansson, E. (2018). Hip complaints differ across age and sex: A population-based reference data for the Hip disability and Osteoarthritis Outcome Score (HOOS). Health and Quality of Life Outcomes, 16, 200. https://doi.org/10.1186/s12955-018-1022-8

Tangtrakulwanich, B., et al. (2026). Minimal clinically important difference in the Hip disability and Osteoarthritis Outcome Score at 3 and 6 months after total hip arthroplasty. Journal of Orthopaedic Surgery. https://doi.org/10.1177/10225536261433423

Wylde, V., et al. (2024). Clinical relevance of patient-reported outcome measures in total hip arthroplasty: A systematic review of MCID, MIC, CID, MDC and PASS. Archives of Orthopaedic and Trauma Surgery. https://doi.org/10.1007/s00402-024-05579-w