What is a Lung Function Test and its purpose?

A lung function test measures how well air moves in and out of your lungs. The most common test is spirometry.

During spirometry, you breathe into a device that records how much air you can blow out and how quickly you can do it. The technician will guide you through the test and may ask you to repeat it a few times to get a clear result.

Your GP may request lung function testing if you have:

• Shortness of breath
• Wheezing
• Ongoing cough
• Chest tightness
• Suspected asthma
• Suspected COPD
• Symptoms after a respiratory infection
• Monitoring for an existing lung condition

A lung function test does not diagnose every condition on its own. It gives your GP useful information to compare with your symptoms, medical history and examination.

Why results can look confusing

Lung function reports usually include numbers, percentages and graphs and it is common to feel a little unsure when you first see them.

Your report may compare your results with expected values for someone of a similar age, height and sex.

Two people can have similar symptoms but different test results. Someone with asthma may show airflow that improves after medication, an individual with COPD can show a different pattern and another may have normal results but still need review because symptoms are ongoing.

Your GP looks at the overall pattern, not just one number, for this reason.

What does FEV1 and FVC mean?

When you get your lung function results back, two of the main numbers you’ll see are FEV1 and FVC. They can look technical, but they’re actually quite straightforward once you break them down.

FEV1 stands for forced expiratory volume in one second. It measures how much air you can forcefully blow out in the first second of the test.

FVC stands for forced vital capacity. It measures the total amount of air you can blow out after taking a deep breath in, showing how much air your lungs can hold and release overall.

Your GP is usually looking at two things:

• How fast you can breathe out (FEV1)
• How much air you can breathe out in total (FVC)

If your FEV1 is lower than expected, it can mean your airways are a bit narrowed or inflamed, which can happen with conditions like asthma or COPD (Chronic Obstructive Pulmonary Disease). If your FVC is lower, it may suggest your lungs aren’t expanding or emptying as fully as they should.

Again, these numbers are not read in isolation. Your GP will look at them alongside your symptoms, medical history and other results.

What the FEV1 FVC ratio shows

The FEV1 FVC ratio compares how much air you blow out in the first second with the total amount you blow out.

The ratio simply helps identify airflow obstruction and if air is having trouble moving out of the lungs quickly for your GP to use when assessing asthma, COPD or other airway problems.

The report and your GOP will also consider how you felt during the test. If you coughed, felt nervous or could not seal your lips around the mouthpiece, the result may be affected. This is why our technicians will guide you through repeat attempts so the report reflects your best effort on the day.

What is a Bronchodilator Test?

You could be asked to use an inhaled medication during the appointment, then repeat the breathing test. This is called bronchodilator response testing.

It helps show if airflow improves after medication. A clear change may support an asthma diagnosis or help guide treatment.

Little change after the medication does not automatically mean treatment will not help. Your GP will review the full picture before talking through the next step.

When will my GP get my Lung Function test results?

Waiting for answers can feel distressing for a lot of people when your or your child’s breathing isn’t quite right and you’re not sure why.

We prioritise a turnaround of results to be sent back to your GP within 24-48 hours. If anything needs urgent attention, your doctor is directly contacted even sooner by us, so that they can follow up with you promptly.

When your GP reviews the report, they’ll explain what it means in the context of your symptoms and will include discussing treatment options, checking how you’re using inhalers or deciding if any further testing or specialist input is required.

Local access to Lung Function Testing

SmartCare Diagnostics provides lung function testing in our diagnostic clinics across several locations, including Springfield, Ipswich, Mt Gravatt, North Lakes and Capalaba.

Many patients are referred after noticing ongoing symptoms like breathlessness or a persistent cough, and being able to attend a nearby clinic can make the process feel more manageable. Shorter travel times and familiar locations can help reduce stress, especially when you’re already dealing with uncomfortable symptoms or juggling daily commitments.

• All referrals accepted
• Bulk billing for eligible Medicare card holders
• Spirometry and bronchodilator testing available
• Other respiratory testing for asthma and COPD assessment
• Routine reports generally returned within 24-48 hours
• Urgent findings communicated promptly to referring doctors

FAQs about Lung Function Tests