Warnings Schwarnings

This is one of the new, more explicit graphics for cigarette package labels, released by Health Canada on Dec. 30, 2010. The. U.S. isn’t the first country to require graphic cigarette labels on packs. We look around the world at what over countries are doing. In recent years, 30 countries or jurisdictions have introduced similar labels. (AP Photo/The Canadian Press, Health Canada)

Question: Do warning labels, even explicit ones like this, reduce smoking?