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Questions and answers

Is a number a diagnosis?

It is natural to worry when you see a number flagged in red on a test report. But one number on its own is not a diagnosis.

Last updated: ~1 min read
One piece is not the whole picture
Figure 1.One piece is not the whole picture

01Short answer

Every number in a test is one piece of a whole picture. A diagnosis is made after the doctor weighs the examination, symptoms, several tests and, if needed, bone marrow and genetic tests together. An abnormal value can come from an infection, medicines, dehydration, lab differences or the expected effect of treatment. What matters is the trend and the context. Discuss a worrying result with your team.

02Simple explanation

One number is a snapshot, not the whole film.

The doctor puts several “snapshots” together before deciding.

03Scientific explanation

A reference range usually covers about 95% of healthy people, so some healthy people also fall slightly outside it.

During leukemia treatment low counts are often expected and are a result of the treatment working.

04What happens in the body?

Why one number is not enough

The same number can be normal in one person and a reason for attention in another. Age, medicines, treatment stage and earlier results are taken into account.

The trend

The direction a value is moving is often more important than the value itself. Results recorded with dates help the conversation with the doctor.

A trend over time — Is a number a diagnosis?
Figure 2.A trend over time — Is a number a diagnosis?

What to do

Write down the worrying result and ask your doctor: “What does this mean in my situation and what should I do?” If you have a fever, bleeding or feel unwell, do not wait.

A doctor looking at the whole picture
Figure 3.A doctor looking at the whole picture

05From a number to a conclusion

How the doctor thinks it through.

One result — One value is outside the range.1One resultOne value is outside the range.
Context — Symptoms and treatment stage are considered.2ContextSymptoms and treatment stage are considered.
Trend — Compared with earlier results.3TrendCompared with earlier results.
The doctor explains — A decision based on the whole picture.4The doctor explainsA decision based on the whole picture.
Less worryKnowing the context reduces fear.
Better conversationsPrepared questions save time.

06Key points at a glance

TopicIn brief
Why one number is not enoughThe same number can be normal in one person and a reason for attention in another. Age, medicines, treatment stage and earlier results are taken into account.
The trendThe direction a value is moving is often more important than the value itself. Results recorded with dates help the conversation with the doctor.
What to doWrite down the worrying result and ask your doctor: “What does this mean in my situation and what should I do?” If you have a fever, bleeding or feel unwell, do not wait.

07Key terms

Reference range
Values found in most healthy people.
Trend
The direction results move over time.
Context
Extra information needed to interpret a result.

08Key points

  • One number is not a diagnosis.
  • Context and trend matter.
  • Low counts can be expected during treatment.
  • Discuss worrying results with your doctor.

09Frequently asked questions

My result is red. What should I do?

Do not panic; tell your team, and call at once if there are urgent signs.

Can I search the number online?

For general information yes, but your own result should be interpreted by your doctor.

10Questions for your doctor

Take these questions to your appointment. The ones you save are collected on the “My questions” page and stay on this device only.

  1. My result is red. What should I do?

  2. Can I search the number online?

My questions

12Sources

  1. MedlinePlus (U.S. National Library of Medicine). How to Understand Your Lab Results
  2. MedlinePlus (U.S. National Library of Medicine). Complete Blood Count (CBC)
  3. National Cancer Institute (NCI). Questions to Ask Your Doctor about Your Diagnosis
  4. National Cancer Institute (NCI). Bleeding and Bruising (Thrombocytopenia) and Cancer Treatment
  5. NHS (UK). Acute myeloid leukaemia
  6. National Cancer Institute (NCI). Common Cancer Myths and Misconceptions
  7. American Cancer Society. Typical Treatment of Acute Myeloid Leukemia (Except APL)
  8. National Cancer Institute (NCI). Nutrition in Cancer Care (PDQ®) – Patient Version
  9. NHS. Chemotherapy
  10. World Health Organization (WHO). Sepsis — fact sheet
Medical disclaimerThis information is for educational purposes only and does not replace medical advice.
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