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OSA50 Questionnaire

5-question sleep apnoea screening — validated for Australian Medicare direct-referral criteria

📋 This page provides general information only — not medical advice. Your GP or healthcare provider knows your individual circumstances and history. Always follow their personalised advice.

The OSA50 is a validated screening tool for obstructive sleep apnoea (OSA). A score of 5 or more, combined with an Epworth Sleepiness Scale score of 8 or more, meets Medicare criteria for your GP to refer you directly for a sleep study — no specialist visit needed first.

1. Obesity 3 points if yes
Is your BMI greater than 35? (BMI = weight in kg ÷ height in metres²)
2. Snoring 1 point if yes
Do you snore loudly (louder than talking, or loud enough to be heard through closed doors)?
3. Apnoeas 2 points if yes
Has anyone observed you stop breathing, gasp, or choke during sleep?
4. Age 1 point if yes
Are you 50 years of age or older?
5. Blood pressure 1 point if yes
Do you have high blood pressure (hypertension), or are you being treated for high blood pressure?
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out of 8
Answer all questions to see your score
📋 Also complete the Epworth Sleepiness Scale

The Medicare direct-referral criteria require both an OSA50 score ≥5 and an Epworth score ≥8. Complete both and share the results with your GP.

Go to Epworth Sleepiness Scale →

About the OSA50

Developed and validated by Chai-Coetzer et al. (2011) in an Australian primary care setting. Designed to identify moderate-to-severe OSA in adults, particularly in primary care. The tool gives extra weight to obesity (3 points) as the strongest single predictor of OSA severity.

Maximum score: 8 (3 + 1 + 2 + 1 + 1). A score of 5 or more has the best sensitivity/specificity balance for identifying moderate-to-severe OSA (AHI ≥15).

Limitation: Screening tools cannot diagnose sleep apnoea — only a sleep study can. A low score does not rule out OSA, particularly in women and younger adults who may present atypically.

OSA50 Scoring

Question Points (if Yes)
Obesity (BMI >35)3
Snoring (loud)1
Apnoeas (observed)2
Age ≥501
Blood pressure (high / treated)1
Total8
Medicare threshold: Score ≥5 + Epworth ≥8 = high probability of moderate-to-severe OSA → GP can refer directly for sleep study (MBS 12203 or 12250)

Frequently asked questions

What does a sleep study involve?

A sleep study monitors your breathing, oxygen levels, heart rate, brain activity, and body movements while you sleep. A home study uses a portable device; an in-lab study is done at a sleep clinic overnight with a technician present. Your GP will recommend which type is appropriate. Learn more about sleep studies →

Is OSA50 better than STOP-Bang?

Neither is definitively better — both are validated and both meet Medicare referral criteria when combined with Epworth ≥8. OSA50 gives more weight to obesity; STOP-Bang includes neck circumference and sex. Your GP may use one or both.

Can I have sleep apnoea with a low score?

Yes. Screening tools are designed to identify high-probability cases, but OSA can occur in people who score low — particularly women, younger adults, and those with mild disease. If you have significant symptoms, discuss them with your GP regardless of your score.

Clinical tool — not a diagnosis. This calculator is for screening and educational purposes only. It cannot diagnose sleep apnoea. Results should be interpreted by a qualified clinician in the context of your full clinical history. A sleep study is required for diagnosis.