The Oxford Shoulder Instability Score, or OSIS, is a 12-item patient-reported outcome measure developed for people with shoulder instability, including dislocation and subluxation presentations. Each item is scored from 0 to 4, giving a total score from 0 to 48, where higher scores indicate better shoulder function and fewer instability-related problems. The OSIS can support monitoring and progress tracking, but it does not diagnose shoulder instability or clear someone for sport on its own.

Introduction

Shoulder instability can affect reaching, dressing, lifting, sleep, gym training, contact sport, overhead sport, throwing, confidence and willingness to use the arm in vulnerable positions.

The Oxford Shoulder Instability Score, commonly called OSIS or OISS, is a patient-reported outcome measure designed specifically for shoulder instability.

It is commonly used for:

• shoulder instability monitoring
• recurrent shoulder dislocation
• shoulder subluxation
• apprehension or worry about instability
• post-stabilisation surgery follow-up
• non-surgical instability management
• return-to-training monitoring
• return-to-sport progress tracking
• research and outcome reporting

Oxford University Innovation describes the OSIS as a short, 12-item, condition-specific patient-reported outcome measure developed and validated for surgical and non-surgical outcomes in people presenting with unidirectional or multidirectional shoulder instability.  

Quick Summary

• Outcome measure: Oxford Shoulder Instability Score
• Abbreviations: OSIS, OISS
• Body region: Shoulder
• Type: Patient-reported outcome measure
• Number of items: 12
• Item score: 0–4
• Total score range: 0–48
• Higher score means: Better shoulder function and fewer instability-related problems
• Lower score means: Greater reported instability-related limitation
• Best used for: Shoulder instability, dislocation, subluxation and stabilisation follow-up
• Key limitation: OSIS does not diagnose shoulder instability or determine return-to-sport readiness on its own

What Is the Oxford Shoulder Instability Score?

The OSIS is a shoulder instability-specific questionnaire.

It was developed to measure outcomes in people with shoulder instability, including people with recurrent dislocation, subluxation or instability-related symptoms.

The OSIS includes 12 items with five response options each. The items capture instability-related concerns across:

• dislocation or slipping episodes
• pain
• daily activities
• dressing
• lifting
• sport or activity limitation
• confidence
• sleep or symptom impact
• work or usual activity impact

A 2024 Springer reference entry describes the OSIS as a 12-item patient-reported measure covering shoulder dislocation or subluxation events, pain and function in one composite scale.  

Why It Is Used

The OSIS is used because shoulder instability can affect more than strength or range of motion.

A client may have good shoulder motion and strength but still report:

• fear that the shoulder will slip
• apprehension in overhead or abducted positions
• reduced confidence with contact sport
• difficulty dressing
• avoidance of throwing
• worry with gym pressing
• reduced confidence sleeping or rolling
• fear during falls or sudden arm movements

The OSIS can help professionals:

• establish a baseline
• quantify self-reported shoulder instability impact
• monitor change over time
• track symptoms after dislocation or subluxation
• monitor post-operative progress
• support education and goal setting
• combine self-reported findings with physical testing
• improve progress reporting in Measurz

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

What It Measures

The OSIS measures the client’s perceived shoulder instability-related symptoms, function and confidence.

It may provide insight into:

• frequency of slipping or dislocation episodes
• pain related to shoulder instability
• difficulty with daily activities
• difficulty with dressing
• difficulty with lifting or carrying
• sport or recreation limitation
• worry about the shoulder
• confidence using the arm
• perceived impact on usual activity

It does not directly measure:

• labral integrity
• capsular laxity
• bone loss
• rotator cuff strength
• scapular control
• neurological status
• tissue healing
• readiness to return to contact sport
• readiness to return to overhead sport

Who It Is Useful For

The OSIS may be useful for:

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

It may be relevant for clients with:

• recurrent shoulder dislocation
• shoulder subluxation
• traumatic shoulder instability
• atraumatic shoulder instability
• multidirectional instability
• post-stabilisation surgery recovery
• apprehension during overhead or sport tasks
• reduced confidence with contact or collision sport
• instability-related activity limitation

The OSIS is condition-specific, so it is more suitable for shoulder instability than broad shoulder pain measures when instability is the main concern.

When to Use This Outcome Measure

Use the OSIS when you want to understand how shoulder instability affects symptoms, function and confidence.

It may be useful at:

• initial assessment
• onboarding
• post-dislocation baseline
• post-subluxation baseline
• reassessment
• post-operative milestones
• return-to-gym planning
• return-to-contact training planning
• return-to-overhead sport planning
• discharge or progress review

The OSIS 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:

• shoulder instability is not the main problem
• the client has general shoulder pain without instability symptoms
• the client cannot complete the questionnaire independently
• language or literacy affects responses
• the wrong language version is used
• multiple body regions are driving limitation
• many items are missing
• the score is being used as a diagnosis
• the score is being used as a pass/fail return-to-sport decision

The OSIS should not be used to:

• diagnose shoulder instability
• confirm labral injury
• confirm structural shoulder damage
• determine bone loss
• determine tissue healing
• identify the exact cause of symptoms
• clear someone for work, training or sport
• replace physical assessment
• replace professional judgement

Equipment or Resources Required

• Oxford Shoulder Instability Score questionnaire
• OSIS scoring guide
• Measurz recording workflow
• Client-reported symptom notes
• Baseline and retest dates
• Optional related physical tests, such as:
  • shoulder range of motion
  • shoulder strength testing
  • apprehension-related testing where appropriate
  • relocation or instability-related tests where appropriate
  • scapular control observation
  • closed-chain upper limb testing
  • contact or overhead exposure notes
  • sport-specific confidence notes
  • pain score

Administration Protocol / Practice

Setup

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

Example wording:

“This questionnaire helps us understand how your shoulder instability is affecting your symptoms, confidence and daily or sport activities. It does not diagnose the cause of instability on its own, but it helps us monitor change over time.”

Format

The OSIS can be completed:

• on paper
• digitally
• independently
• verbally if assistance is needed
• before a session
• during reassessment
• as part of a Measurz workflow

Client Instructions

Ask the client to:

• answer based on their affected shoulder
• select right or left shoulder where the form requires it
• choose one response per item
• answer based on the recall period in each question
• answer every item where possible
• ask for clarification if they do not understand wording
• complete the same version at each retest

The Oxford University Hospitals form includes different recall periods across items, including one question about slipping or dislocation episodes during the last 6 months and several questions about symptoms or function during the last 3 months.  

Completion Method

Record whether the OSIS was completed:

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

This supports repeatability and helps interpret change over time.

Assistance Rules

If assistance is needed:

• explain instructions without leading the answer
• avoid telling the client which score to choose
• avoid prompting the client toward a “better” or “worse” response
• record that assistance was provided
• use the same assistance approach at retest where possible

Missing Item Handling

Do not guess missing responses.

For best practice:

• encourage completion of all 12 items
• record any missing item
• avoid comparing scores if missing-item handling differs between sessions
• record whether the score was calculated from a complete or incomplete form
• interpret incomplete scores cautiously

Scoring Process

The OSIS includes 12 items.

Each item is scored from:

• 0: worst response
• 4: best response

The total score is calculated by adding all 12 item scores.

Score range:

• Minimum: 0
• Maximum: 48

Scoring direction:

• Higher score: better outcome / better reported shoulder function
• Lower score: greater instability-related limitation

Oxford University Innovation scoring guidance states that each OSIS question should be scored 0 to 4, with 4 representing the best outcome, and that summed scores run from 0 to 48, with 48 being the best outcome.  

Retesting Considerations

Retest at meaningful points, such as:

• baseline
• after a rehabilitation block
• after a subluxation or dislocation event
• before return to gym loading
• before return to contact training
• before return to overhead sport
• post-operative milestones
• discharge or progress review

For consistency, record:

• date
• affected side
• dominant side
• recent instability events
• current sport or training exposure
• contact or overhead exposure
• recent flare-ups
• current confidence
• current restrictions
• any major changes in activity demands

Safety Notes

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

However, worsening responses may support further assessment where the client reports:

• repeated slipping or dislocation episodes
• increasing apprehension
• worsening pain
• major loss of confidence
• increasing activity avoidance
• reduced function despite training progress
• new neurological symptoms

Scoring and Interpretation

The OSIS produces a total score from 0 to 48.

Higher scores indicate better reported shoulder function and fewer instability-related problems.

Lower scores indicate greater reported instability-related symptoms or limitation.

Score Range

• 0: greatest reported instability-related difficulty
• 48: best reported shoulder status on the questionnaire

What a High Score May Suggest

A higher OSIS score may suggest:

• fewer instability-related problems
• better shoulder confidence
• better daily function
• less pain or worry
• better tolerance of activity
• fewer limitations with sport or usual tasks

What a Low Score May Suggest

A lower OSIS score may suggest:

• more instability-related limitation
• more worry about the shoulder slipping
• more pain or functional restriction
• reduced confidence
• reduced sport or recreation tolerance
• greater impact on daily activity

What the Score Does Not Prove

An OSIS score does not prove:

• the diagnosis
• labral injury
• capsular laxity
• bone loss
• shoulder structural stability
• tissue healing
• readiness to return to sport
• whether imaging is required
• whether one intervention caused the change

How to Explain the Result Safely

Example wording:

“Your OSIS score suggests your shoulder instability is still affecting confidence and activity. This does not tell us exactly what structure is involved, but it helps us track how your symptoms and confidence change over time.”

What the Score May Mean in Different Client Populations

General Fitness Clients

For general fitness clients, OSIS may help show how instability affects:

• gym pressing
• overhead lifting
• carrying
• dressing
• sleep
• confidence using the arm
• avoiding certain positions

Interpretation cautions:

• recent instability episodes may strongly influence scores
• pain from non-instability shoulder conditions may affect responses
• physical capacity should still be assessed

Sport and Performance Clients

For athletes, OSIS is especially useful when instability affects confidence and participation.

It may help monitor:

• contact confidence
• overhead confidence
• throwing or serving tolerance
• apprehension in sport positions
• avoidance of specific drills
• confidence after dislocation or subluxation
• readiness discussions alongside objective testing

A high OSIS score should not be treated as return-to-sport clearance on its own.

Contact and Collision Sport Clients

For contact or collision sport clients, interpretation should consider:

• tackling exposure
• falling exposure
• opponent contact
• training contact progression
• apprehension under fatigue
• protective bracing or taping use
• medical or surgical guidance where relevant

Overhead Sport Clients

For overhead athletes, interpretation should consider:

• throwing volume
• serving volume
• overhead velocity
• end-range confidence
• fatigue response
• shoulder strength and control
• sport-specific exposure

Post-Surgical Stabilisation Clients

For post-operative clients, OSIS can help monitor perceived stability, function and confidence over time.

Interpretation should consider:

• surgery type
• healing stage
• restrictions
• rehabilitation phase
• return-to-contact or overhead timeline
• medical or surgical guidance
• current sport exposure

Multidirectional or Atraumatic Instability Clients

For multidirectional or atraumatic instability, OSIS may help monitor perceived instability impact.

Interpretation should also consider:

• symptom irritability
• generalised laxity if relevant
• strength and control
• load tolerance
• movement confidence
• functional goals

Meaningful Change, MCID, MDC and Responsiveness

Meaningful change helps determine whether an OSIS score change is likely to matter.

Key terms:

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

OSIS Meaningful Change Evidence

A 2021 study reported that literature on MCID values for shoulder instability PROMs was limited and that no previous MCID had addressed OSIS. The study was designed to determine the MCID for OSIS after arthroscopic Bankart repair.  

Because meaningful change values are context-specific, OSIS MCID values should be interpreted according to:

• shoulder instability type
• surgical versus non-surgical context
• follow-up timeframe
• baseline score
• sport demands
• scoring method
• population studied

Practical Interpretation

When interpreting OSIS change:

• compare the total score with baseline
• check whether the change exceeds available MCID or MDC values for a matching population
• check whether instability episodes have reduced
• compare with pain, confidence and sport exposure
• consider strength, ROM and functional test findings
• avoid over-interpreting very small changes

When Values Are Uncertain

Reported meaningful change values may vary by:

• traumatic versus atraumatic instability
• unidirectional versus multidirectional instability
• surgical versus non-surgical management
• contact versus non-contact sport
• time since dislocation or surgery
• baseline score
• follow-up timeframe

When no matching MCID, MDC or SEM value exists, interpretation should rely more heavily on:

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

Normative Data, Reference Values or Comparative Data

Broad general-population normative values for OSIS are limited because the OSIS is a condition-specific shoulder instability questionnaire.

Evidence level: Level 3 — practical comparison guidance is recommended when exact norms are not available or not applicable.

Use:

• baseline comparison
• retest comparison
• instability event history
• sport exposure
• confidence notes
• pain and symptom response
• related physical assessment findings

Practical guidance:

• Scores closer to 48 generally suggest better shoulder status.
• Lower scores suggest greater instability-related limitation.
• Norms for healthy populations are not the main interpretation method.
• Baseline and repeated measures are usually more useful than one isolated score.
• Compare scores only when the same OSIS version and scoring method are used.
• Avoid using one OSIS score as a return-to-sport threshold.

Comparison should consider:

• age
• sport
• position or role
• contact exposure
• overhead exposure
• dominant side involvement
• instability type
• surgery history
• time since last instability event
• training load

Reliability and Validity

The OSIS was developed and validated as a shoulder instability-specific patient-reported outcome measure.

Oxford University Innovation states that the OSIS is practical, reliable, valid and sensitive to clinically important change.  

An ISPOR presentation database summary of the original development and validation reported:

• Cronbach’s alpha of 0.91 at pre-treatment assessment and 0.92 at follow-up
• high test-retest correlation of r = 0.97
• coefficient of reliability of 5.7
• construct validity through correlation with Constant and Rowe clinical scores
• responsiveness with a large standardised effect size of 0.8 or greater  

The OSIS has also been translated and validated in other languages. For example, a 2020 Arabic validation paper describes OSIS as a 12-question instrument used in shoulder instability research and evaluated validity and reliability of the translated version.  

Reliability and validity are stronger when:

• the correct OSIS version is used
• the correct language version is used
• all 12 items are completed
• the same scoring method is repeated
• the affected side is clearly recorded
• retesting occurs at meaningful time points
• results are interpreted alongside physical and sport-specific assessment

Interpret cautiously when:

• multiple items are missing
• the client has general shoulder pain rather than instability
• recent sport exposure has changed substantially
• the client has not attempted feared activities
• the score is used as a stand-alone diagnosis or clearance decision
• the language version has limited validation evidence

Common Errors and Limitations

Common errors include:

• treating OSIS as a diagnosis
• using OSIS as return-to-sport clearance
• not recording affected side
• not recording dominance
• not recording recent instability events
• ignoring sport or contact exposure
• not recording completion method
• ignoring missing items
• over-interpreting small changes
• failing to pair it with physical testing

Limitations include:

• self-report can be influenced by recent instability episodes, pain or confidence
• scores do not identify the exact structural cause of instability
• broad normative values are limited
• meaningful change values vary by population and treatment context
• sport-specific readiness requires additional testing
• high scores do not guarantee safety in contact or overhead sport
• it should be paired with physical assessment, history and client goals

Practical Applications

The OSIS may help professionals:

• document baseline shoulder instability impact
• monitor change after dislocation or subluxation
• track perceived confidence and function
• monitor post-operative stabilisation progress
• support return-to-gym discussions
• support return-to-sport planning
• guide client education
• improve communication with coaches or support teams
• strengthen Measurz reports

For fitness clients, OSIS can show whether shoulder instability affects pressing, overhead lifting, carrying or confidence.

For athletes, OSIS can support broader return-to-sport reasoning but should be paired with sport-specific exposure and physical testing.

For post-surgical clients, OSIS can help monitor perceived stability and confidence across rehabilitation phases.

For Measurz users, OSIS is most useful when combined with practical measures such as:

• shoulder range of motion
• shoulder strength
• apprehension-related findings
• closed-chain upper limb tests
• scapular control observations
• pain score
• instability event history
• contact or overhead exposure
• sport-specific confidence notes

How to Record This in Measurz

Record:

• outcome measure name: Oxford Shoulder Instability Score / OSIS / OISS
• version used
• date completed
• completion method: paper, digital, interview or assisted
• language/version used
• condition or presentation being tracked
• affected side: left, right or bilateral
• dominant side
• total score out of 48
• score range: 0–48
• direction of scoring: higher score indicates better outcome
• missing items, if any
• assistance provided, if any
• recent dislocation or subluxation episodes
• current pain score, if relevant
• current symptoms
• current confidence level
• current gym, work or sport exposure
• contact or overhead exposure, if relevant
• key functional limitations
• confidence or participation goals
• baseline comparison
• MCID/MDC comparison where supported
• item-level activities that improved or worsened
• related physical assessment findings
• interpretation notes
• retest date
• referral or further assessment notes where appropriate

Record whether the main limitation appears to be:

• instability episode frequency
• apprehension or worry
• pain dominant
• dressing or daily activity limitation
• lifting or carrying limitation
• overhead activity limitation
• contact sport limitation
• return-to-sport confidence limitation
• mixed instability-related limitation
• 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

• Shoulder Pain and Disability Index / SPADI
• Upper Extremity Functional Index / UEFI
• Neck Disability Index
• Pain Self-Efficacy Questionnaire / PSEQ
• Tampa Scale for Kinesiophobia / TSK
• Fear-Avoidance Beliefs Questionnaire / FABQ
• Örebro Musculoskeletal Pain Screening Questionnaire
• Spine Function Index-10

FAQs

What does the Oxford Shoulder Instability Score measure?

The OSIS measures self-reported symptoms, function and confidence related to shoulder instability, including dislocation or subluxation problems.

How many items are in the OSIS?

The OSIS has 12 items.

How is the OSIS scored?

Each item is scored from 0 to 4. The total score ranges from 0 to 48, with higher scores indicating better shoulder function and fewer instability-related problems.  

Does a higher OSIS score mean better function?

Yes. Higher scores indicate better reported shoulder status.

Does OSIS diagnose shoulder instability?

No. OSIS measures the client’s reported instability-related symptoms and function. It does not diagnose shoulder instability or identify the structural cause.

What is a meaningful change in OSIS?

Meaningful change values should be matched to the population and setting. A 2021 study specifically investigated OSIS MCID after arthroscopic Bankart repair because previous shoulder instability MCID evidence was limited.  

Can OSIS be used for athletes?

Yes, it is useful for athletes with shoulder instability, but it should be paired with sport-specific testing, exposure tracking, strength, ROM, confidence and professional judgement.

Can OSIS clear someone for return to sport?

No. OSIS can support return-to-sport reasoning, but it should not be used as the only clearance measure.

Key Takeaways

• The Oxford Shoulder Instability Score is a 12-item shoulder instability outcome measure.
• Each item is scored from 0 to 4.
• Total scores range from 0 to 48.
• Higher scores indicate better reported shoulder function.
• OSIS is designed for shoulder instability, including dislocation and subluxation contexts.
• OSIS does not diagnose instability or clear a client for sport.
• Normative values are limited, so baseline and retest comparison are usually most useful.
• Measurz should record version, total score, side, dominance, instability events, sport exposure, confidence, baseline comparison and related physical findings.

References

Dawson, J. (2023). Oxford Shoulder Instability Score. In F. Maggino (Ed.), Encyclopedia of Quality of Life and Well-Being Research (pp. 4916–4918). Springer. https://doi.org/10.1007/978-3-031-17299-1_2047

Oxford University Innovation. (2026). The Oxford Shoulder Instability Score (OSIS). https://innovation.ox.ac.uk/licence-details/oxford-shoulder-instability-score-osis

Oxford University Innovation. (n.d.). Scoring system for the Oxford Shoulder Instability Score. https://innovation.ox.ac.uk/wp-content/uploads/2014/09/OSIS_Scoring_System.pdf

Shaha, J. S., Cook, J. B., Song, D. J., Rowles, D. J., Bottoni, C. R., Shaha, S. H., & Tokish, J. M. (2021). Determining the minimal clinically important difference on the Oxford Shoulder Instability Score after arthroscopic Bankart repair. Orthopaedic Journal of Sports Medicine, 9(12), 23259671211060023. https://doi.org/10.1177/23259671211060023

Shahien, A., Azzam, W., Kamel, M., & El-Sayed, M. (2020). Validity and reliability of the Oxford Shoulder Instability Score questionnaire in Arabic. Journal of Musculoskeletal Disorders and Treatment, 6, 082.

Werthel, J. D., Sabatier, V., Schoch, B., et al. (2022). Patient-reported outcome measures for shoulder instability: A systematic review. Journal of Shoulder and Elbow Surgery.