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.
The subgroup and interaction analyses for dietary niacin intake on COPD. Stratified logistic regression analysis to identify variables that modify the correlation between dietary niacin intake and COPD. A subgroup and interaction analyses with dietary niacin intake as a categorical variable (divided into quarters), compared Q4 with Q1. Adjusted for age, race, annual family income, smoking status, hypertension, diabetes, marital status, drinking status.
