Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Assumptions in models of gene-environment interactions in chronic obstructive pulmonary disease (COPD). BODE, multidimensional index including body mass index, airflow obstruction, dyspnea, and exercise capacity index. Adapted from Caspi and Moffitt (2006).
