A pack-year is a clinical quantification of cigarette smoking used to measure a person’s exposure to tobacco.
This concept is used to assess a person’s risk of developing lung cancer or other pathologies related to tobacco use.
Formula to calculate pack years.
Suppose a person smokes 1 pack of cigarettes everyday for 3 years. Calculate his pack years.
Since there are 20 cigarettes in a pack therefore;
Thus, the person’s pack years are 3.