Understanding your medical notes
Blood test results explained: how to read yours in plain English
Got a results sheet full of three-letter codes, numbers, and the odd "H" or "L" next to them? This guide explains what reference ranges actually mean, why a flagged value often isn't cause for alarm, and what the most common tests are checking — so you can read your results with confidence.
Skip the decoding — get your results explained in seconds
Paste your blood test results (or upload a photo, PDF, or Word file) and Patiently AI explains each value in plain English, including what high and low can mean. Free, no account, and identifying details are removed on your device first.
Explain my blood test → Your text isn't stored. Available on web, iOS & Android.How a blood test result sheet is laid out
Almost every results sheet has the same four columns: the test name (often abbreviated), your result, the units, and the reference range for that test. A flag — usually H (high) or L (low) — appears when your result falls outside the range. Read across one row at a time and it becomes far less overwhelming.
What a "reference range" really means
The reference range (or "normal range") is the span of values found in most healthy people. It's deliberately set to include the large majority — but not everyone — which has two important consequences:
- A result just outside the range can still be completely normal for you.
- Ranges differ slightly between labs and can depend on age and sex, so always read the range printed on your sheet rather than one from the internet.
What matters most is how far outside the range a value is, whether it's changing over time, and how it fits with your symptoms — which is why results are interpreted by your GP, not in isolation.
Common blood tests and what they check
| Abbreviation | What it measures |
|---|---|
| FBC / CBC | Full / complete blood count — red cells, white cells, and platelets |
| Hb | Haemoglobin — oxygen-carrying protein; low can mean anaemia |
| WBC | White blood cell count — part of your immune system |
| PLT | Platelets — help your blood clot |
| U&E | Urea & electrolytes — kidney function and salt balance |
| eGFR | Estimated kidney filtration rate (higher is generally better) |
| LFT | Liver function tests (includes ALT, ALP, bilirubin) |
| HbA1c | Average blood sugar over ~3 months — used for diabetes |
| TSH | Thyroid-stimulating hormone — thyroid function |
| CRP | C-reactive protein — a marker of inflammation |
| ESR | Erythrocyte sedimentation rate — another inflammation marker |
| Ferritin | Iron stores — low can indicate iron deficiency |
| Chol / LDL / HDL / TG | Cholesterol panel — total, "bad", "good", and triglycerides |
Seeing a code that isn't here? Patiently AI's built-in medical glossary covers over 9,000 terms — or paste the full results sheet in and it explains every line in context.
How to read your blood test results, step by step
- Go row by row. For each test, look at your result, the units, and the range on the same line.
- Spot the flags. Note anything marked H or L — these are the values worth asking about.
- Check how far out it is. A value a fraction outside the range is very different from one well outside.
- Look for a trend if you have previous results — direction of travel often matters more than a single number.
- List your questions for your GP using the prompts below.
Don't guess what "H" next to your result means
Patiently AI turns "Hb 102 g/L (L)" into "Your haemoglobin is a little low, which can be a sign of anaemia — worth discussing with your GP." It does that for every line of your results.
Try it with your own results → Paste, upload, or photograph your results sheet.Questions to ask your GP about your blood test
- Which of my results are outside the normal range, and by how much?
- Is a flagged result something to act on, or within normal variation for me?
- How does this compare with my previous results?
- Do I need a repeat test or any follow-up, and when?
- Could any of my medicines or recent illness have affected these results?
Patiently AI generates personalised "Questions for your doctor" automatically from your results — so you walk into your next appointment prepared.
Frequently asked questions
What does a reference range on a blood test mean?
It's the span of values seen in most healthy people for that test. Your result is compared against it, and anything outside is flagged High (H) or Low (L). Ranges vary slightly between labs and can depend on age and sex, which is why your sheet shows the specific range used for your sample.
Is a result outside the normal range something to worry about?
Not necessarily. A value can sit just outside the range and be harmless, because the range includes most — but not all — healthy people. What matters is how far outside it is, the trend over time, and the whole clinical picture. Interpret a flagged result with your GP rather than alone.
What is an FBC or Full Blood Count?
An FBC (CBC in the US) measures the cells in your blood: red cells and haemoglobin (Hb) which carry oxygen, white cells (WBC) which fight infection, and platelets (PLT) which help clotting. It screens for things like anaemia, infection, and clotting problems.
What does eGFR mean on my results?
eGFR (estimated glomerular filtration rate) measures how well your kidneys filter, calculated from a marker called creatinine. Higher is generally better. It's an estimate, so a single slightly low value isn't necessarily significant — your GP looks at the trend.
Can Patiently AI explain my blood test results?
Yes. Paste your results — or upload a photo, PDF, or Word file — and Patiently AI explains each test in plain English, tells you what high and low values can indicate, and suggests questions to ask your doctor. It's free, needs no account, and removes identifying details on your device before processing.