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🌬️ Predicted Peak Expiratory Flow (Adult)

UseBedside peak-flow reference in asthma. Personal best beats a population predicted value.

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StrataCommon asthma zones: ≥80% green, 50–79% yellow, <50% red (use personal best). This is not an NHANES spirometr…

LimitsDerived mainly in adults ~15–85 years. · Children and extreme height/ethnicity increase error. · Acute asthma also needs symptoms and SpO₂.

SourceNunn AJ, Gregg I. New regression equations for predicting peak expiratory flow in adults. BMJ 1989;…

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.

Paste the link in Slack, Teams, X, or LinkedIn — the preview image comes from this page’s Open Graph card.

Methodology · worked example, guidelines & full notes
Clinical takeaway

Nunn & Gregg, not NHANES.

When to use

Bedside peak-flow reference in asthma. Personal best beats a population predicted value.

How it works

Men: ln(PEF)=0.544 ln(age)−0.0151×age−74.7/height+5.48 Women: ln(PEF)=0.376 ln(age)−0.0120×age−58.8/height+5.63 Height cm, PEF L/min.

Key points

  • Nunn & Gregg, not NHANES.
  • Can show % predicted.
  • Prefer personal-best PEFR.

References

  • Nunn AJ, Gregg I. New regression equations for predicting peak expiratory flow in adults. BMJ 1989;298:1068-1070

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.

SexMale
Age40 years
Height170 cm
Measured PEFR (optional)450 L/min

→% predicted72%

  • Predicted PEFR：629 L/min
  • Measured：450 L/min
  • Common asthma zones：Yellow (50–79%)
SexFemale
Age40 years
Height170 cm
Measured PEFR (optional)450 L/min

→% predicted92%

  • Predicted PEFR：488 L/min
  • Measured：450 L/min
  • Common asthma zones：Green (≥80%)
Verification & sources · governance
FAQ

Frequently asked questions

Does Predicted Peak Expiratory Flow (Adult) 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 Predicted Peak Expiratory Flow (Adult) calculated in practice? Can you show a worked example?
Inputs: Sex Male, Age 40 years, Height 170 cm, Measured PEFR (optional) 450 L/min → Result: % predicted 72 %（Predicted PEFR: 629 L/min, Measured: 450 L/min, Common asthma zones: Yellow (50–79%)） Inputs: Sex Female, Age 40 years, Height 170 cm, Measured PEFR (optional) 450 L/min → Result: % predicted 92 %（Predicted PEFR: 488 L/min, Measured: 450 L/min, Common asthma zones: Green (≥80%)）
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