Since then, these bans have become trendy on college campuses across the country. All of the schools in the University System of Maryland will be smoke-free by the start of next school year, as will be George Washington and American universities in the District. Nationally, more than 800 schools have banned smoking — and more than 600 of those schools forbid all tobacco products.

(Chris Goodney/Bloomberg)

Do these bans work? Do they change students’ behavior and attitudes?

When the Indiana University in Bloomington announced that it would ban smoking starting in January 2008, health science researchers at the university decided to study the topic. They compared their home campus, where smoking would soon not be allowed anywhere, to nearby Purdue University in West Lafayette, where smoking was allowed as long as smokers stayed at least 30 feet away from buildings.

They recruited instructors at each university to invite students in their classes to participate in a paper-and-pencil survey during the fall of 2007 and then again in fall 2009. More than 3,200 students participated in each survey. The researchers also had a pool of 301 Indiana students and 231 Purdue students who completed online surveys at the beginning of the fall 2008, spring 2009 and fall 2009 semesters.

The researchers found that Indiana students who lived under the ban had a marked change in their attitudes about smoking and their smoking habits, while things at Purdue stayed mostly the same.

The researchers, led by associate professor Dong-Chul Seo, noted that Indiana’s smoking ban wasn’t strictly enforced.

“The positive changes may be attributable to increased awareness of the policy due to signage an media coverage,” the team of researchers wrote in an article published online in the journal Preventive Medicine in 2011. An awareness campaign included a campus bus that was “completely wrapped with anti-tobacco messaging.”

The researchers also note that their research subjects were volunteers and were largely white Midwesterners, “so caution is warranted in generalization to college students in other regions.” But, in short, the researchers wrote that “these results are encouraging for university administrators considering stronger tobacco control policies.”

Some of their findings:

* In 2007, 16.5 percent of Indiana students and 9.5 percent of Purdue students reported that they currently smoked cigarettes. By 2009, Indiana’s percentage of smokers had fallen to 12.8 percent, while Purdue’s rate slightly increased to 10.1 percent.

* For smokers at Indiana, the average number of cigarettes smoked each day was 6.6 in 2007 and 5.9 in 2009. At Purdue, it was 5.2 in 2007 and 6.8 two years later.

* In 2007, nearly three-quarters of Indiana students who were surveyed reported that at least 26 percent of their peers smoked. By 2009, that number of students reporting dropped to 67 percent. Meanwhile at Purdue, the perception of students that more than a quarter of their classmates smoked increased from 59 percent to 67 percent. At Indiana, there was also a decrease in the number of student who said that at least two of their closest friends smoked.

You can read more about the study here: “Study: Campus smoking ban reduced students’ smoking, changed attitudes.”