Hospital and clinic documents
Spirometry (lung function test) report explainer
A spirometry report is a grid of measured, predicted and percent-of-predicted values, often printed twice: once before an inhaler and once after. Add your report below to see what each row measures and how the columns relate to one another.
Explain your spirometry (lung function test) report
- 1. Add itDrop a PDF, take a photo or paste the text.
- 2. Check itPersonal details are removed on your device. You approve what is sent.
- 3. Read itSummary, table of results, terms and questions to ask.
The explainer opens on its own page with no adverts and no outside scripts. Your file is read on your device and is never uploaded.
What you get
- Each measurement on its own row with the measured, predicted and percent predicted values from your report.
- Before and after bronchodilator results placed side by side, with the change your report states.
- Abbreviations such as FEV1, FVC, PEF, LLN and FEF25-75 written out and defined.
- The interpretation and any note about test quality quoted as written.
Lines you will usually see on a spirometry report
- FVCForced vital capacity, the total amount of air you can blow out after a full breath in
- FEV1Forced expiratory volume in one second, the amount blown out in the first second of that breath
- FEV1/FVC ratioThe share of the total that came out in the first second
- Predicted and % predictedThe value expected for someone of your age, height and sex, and your result as a percentage of it
- LLN and z-scoreThe lower limit of normal, and how far a result sits from the predicted value
- Pre and post bronchodilatorResults before and after an inhaled medicine that opens the airways, with the change in mL and percent
- PEFPeak expiratory flow, the fastest speed reached during the blow
What this tool cannot tell you
Spirometry depends on effort and technique, which is why reports carry quality grades, and a poor-quality test can mislead. Predicted values come from reference equations that differ between laboratories, and pattern words such as obstructive or restrictive describe the shape of the numbers without naming a disease. MedicDecode explains the rows and columns and does not say whether your lungs are healthy. The clinician who ordered the test reads it alongside your symptoms and examination.
Common questions
What does percent predicted mean?
It is your measured value divided by the value expected for a person of your age, height and sex. Laboratories use different reference equations, so the predicted figure can differ from one report to the next.
Why are there two sets of results, pre and post?
The test was repeated after you inhaled a bronchodilator, a medicine that opens the airways. The report gives the change between the two sets and usually states whether it counts as a significant response by the laboratory's own criteria.
My report gives the test a quality grade. What is that?
Each blow is checked for how complete and repeatable it was, and many reports sum this up as a letter grade. A low grade is a warning to read the numbers with caution, and the test is sometimes repeated.
Words you may see on this report
Tap a word for its plain-English meaning, an example line and what it does not mean.
- Dialysis
Dialysis is a treatment that removes waste and extra fluid from the blood when the kidneys can no longer do this well enough.
- Directly observed therapy
Directly observed therapy (DOT) means a health worker watches you take each dose of a medicine, most often for tuberculosis treatment.
- Discharge summary
A discharge summary is a document written when you leave hospital that explains why you were there, what was done, and what happens next.
- Follow-up appointment
A follow-up appointment is a planned visit after a test, treatment or hospital stay to check progress and decide next steps.
- Hemodialysis
Hemodialysis is a treatment where a machine filters the blood to remove waste and extra fluid when the kidneys cannot do it well enough.
- Nil by mouth
Nil by mouth means a person should not eat or drink anything, usually before surgery, a procedure or certain tests.
- Palliative
Palliative means care or treatment focused on easing symptoms and improving quality of life, rather than on removing the illness itself.
- Referral
A referral is when one health professional asks another, usually a specialist or service, to see you or carry out a test.
- Triage
Triage is the process of sorting patients by how urgently they need care, so the most urgent are seen first.
- Vital signs
Vital signs are basic body measurements, such as heart rate, blood pressure, breathing rate, temperature and oxygen level.