"E-Years": A Proposal for Standardized Quantification of Electronic Cigarette Use

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Journal of Medical Practice Management


The prevalence of electronic cigarette (e-cigarette) use and its potentially negative health effects has led to an increasing need for integration of the documentation and screening of e-cigarette use into a routine history and physical examination. This information is imperative to advancing research on the health effects and epidemiology of this increasingly popular product. However, these efforts are limited due to the lack of a standardized method of quantification or common terminology surrounding e-cigarette use. This study analyzed a rapidly growing collection of literature to identify the manner in which e-cigarette use has been quantified and reported in previous studies, variations in e-cigarette products and use, and quantification methods used for traditional cigarettes, in order to develop a standard method of quantification for e-cigarette use. This proposal, similar to cigarette pack-years, quantifies and reports e-cigarette use by volume (mL) of e-liquid consumed per day multiplied by the number of years an individual has used e-cigarette products. This calculation will be referred to as “e-years.” We believe e-years is an appropriate equivalent to pack-years in the reporting of tobacco use and employs patient-friendly calculation and an attractive nomenclature, and, furthermore, propose the utilization of this for standard reporting and documentation of e-cigarette use.

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electronic cigarettes, e-years, pack-years, nicotine, vaping, documentation, quantification