Low-Density Lipoprotein Cholesterol, Serum/Plasma — Calculated, Substance Concentration
A calculated blood test estimates LDL ("bad") cholesterol from other cholesterol results to help assess cardiovascular risk.
["This test estimates LDL cholesterol and helps determine how much cardiovascular risk reduction may be needed."]
Key facts at a glance
- LOINC
- 56139-9
- Short code
- LDL4 SerPl-sCnc
- Synonyms
- LDL4 SerPl-sCnc
- Category
- lipid
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 100
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83721
- SNOMED
- 113079007
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
What is this test?
Low-density lipoprotein (LDL) cholesterol is a type of cholesterol that can build up in artery walls. A calculated LDL result is estimated using a formula based on other measurements, usually total cholesterol, HDL cholesterol, and triglycerides.
Why might I need this test?
Calculated LDL cholesterol is commonly used to assess cardiovascular risk, guide cholesterol-lowering treatment, and monitor progress. It may be part of a routine lipid panel or ordered during follow-up care.
How is the test performed?
A blood sample is collected, usually from a vein in the arm. The laboratory measures the other components of the lipid panel and uses them to calculate the LDL cholesterol value.
How do I prepare for the test?
Fasting may be required when this test is ordered as part of a lipid panel, particularly if triglycerides are elevated. Follow the instructions from your healthcare professional, and do not stop taking cholesterol medication unless specifically advised.
Reference range
Optimal: <100 mg/dLN/A
Fasting for 12-14 hours preferred. Water is permitted. Avoid alcohol for 24 hours before the test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A high calculated LDL result may indicate increased risk of plaque buildup and cardiovascular disease, such as heart attack or stroke. The meaning depends on your overall risk factors, medical history, and treatment goals. A calculated result may not match a direct LDL measurement in some circumstances, so your clinician may confirm it with another test if needed.
Short name
Calculated LDL Cholesterol
Frequently asked questions
Is a calculated LDL cholesterol result the same as a direct LDL measurement?
Does this test require fasting?
Can I lower LDL cholesterol before my appointment?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy