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Updated: Jul 2, 2026

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Exponential cigarette-pack-year index (ECPYI)

Jalal Poorolajal1

  • 1Department of Epidemiology, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran; Modeling of Noncommunicable Diseases Research Center, Institute of Health Sciences and Technologies, Hamadan University of Medical Sciences, Hamadan, Iran; Research Center for Health Sciences, Institute of Health Sciences and Technologies, Hamadan University of Medical Sciences, Hamadan, Iran.

Public Health
|June 29, 2026
PubMed
Summary

A new metric, the Exponential Cigarette-Pack-Year Index (ECPYI), better reflects lung cancer risk from smoking duration than traditional measures. ECPYI accounts for non-linear increases in risk associated with longer smoking history.

Keywords:
Cumulative exposureRisk assessmentSmokingTobacco use

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