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🫀 LDL Cholesterol (Friedewald)

UseEstimate LDL when a direct measurement is unavailable.

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SourceFriedewald WT, et al. Clin Chem 1972

Runs locally in your browser (no PHI uploaded). For licensed clinicians — not a substitute for clinical judgement.
Stored on this device for revisit reminders

This-shift next steps

After scoring: open the scene pack, peer scores, and the matching pathway. Local reference — no HIS write.

Scene next step
📋ASCVD / China-PAROpen scene pack →
Related scores
Matching pathway
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Score + version; reference only — not a substitute for care · no HIS write

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Methodology · worked example, guidelines & full notes
Clinical takeaway

Underestimates LDL at low LDL or high triglycerides.

When to use

Estimate LDL when a direct measurement is unavailable.

How it works

LDL = TC − HDL − TG/5 (mg/dL); invalid at triglycerides ≥ 400 mg/dL.

Key points

  • Underestimates LDL at low LDL or high triglycerides.
  • Use direct LDL or Martin-Hopkins when more accuracy is needed.
  • Requires a fasting sample for best accuracy.

References

Worked calculation

The values below come from this tool's own example placeholders and are computed server-side with the formula shown on this page, so the arithmetic can be checked quickly. It demonstrates how to substitute values only — it is not clinical advice and not a real case.

Total cholesterol200 mg/dL
HDL cholesterol50 mg/dL
Triglycerides150 mg/dL

→Calculated LDL120mg/dL

  • Formula：LDL = TC − HDL − TG/5 (mg/dL)
  • Caution：Underestimates LDL at low LDL or high TG; invalid if TG ≥ 400.
Verification & sources · governance
FAQ

Frequently asked questions

What are the limits and cautions when using LDL Cholesterol (Friedewald)?
For licensed clinicians and clinical researchers. Interpret results with history, investigations and local protocols; not a diagnosis or prescription, and not a substitute for multidisciplinary decision-making or local guidelines.
Does LDL Cholesterol (Friedewald) upload patient data? Where is it calculated?
Calculation runs locally in the browser; inputs and results are not uploaded. For licensed clinicians only; interpret with history, investigations and local protocols — not a diagnosis or prescription.
How is LDL Cholesterol (Friedewald) calculated in practice? Can you show a worked example?
Inputs: Total cholesterol 200 mg/dL, HDL cholesterol 50 mg/dL, Triglycerides 150 mg/dL → Result: Calculated LDL 120 mg/dL（Formula: LDL = TC − HDL − TG/5 (mg/dL), Caution: Underestimates LDL at low LDL or high TG; invalid if TG ≥ 400.）
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