Hankinson and NHANES III

Hankinson used NHANES III pulmonary function data on 7,429 survey participants 8 yr of age and older who did not have symptoms of asthma nor smoked.

NHANES III stands for the National Health and Nutrition Examination Survey III. Completed between 1988 and 1994 it is a sample of approximately 34,000 people living in the United States. For more information see http://www.cdc.gov/nchs/products/elec_prods/subject/nhanes3.htm

LLN stands for the Lower Limit of Normal. It is the lower 5th percentile.