Policies that ban smoking on college campuses can reduce students’ smoking and change their attitudes toward smoking regulations, a new study suggests.

The study compared smoking rates and student attitudes toward smoking policies at Indiana University, which had a campus-wide smoking ban in place, and Purdue University, which did not, according to Science Daily. The study found the student smoking rate at Indiana dropped after the ban was implemented, and those who continued to smoke consumed fewer cigarettes.

The smoking rate at Indiana continued to be higher at Indiana than at Purdue after two years, however. The researchers found the percentage of students who smoked at Indiana dropped 3.7 percent, to 12.8 percent, while the smoking rate increased slightly at Purdue, to 10.1 percent.

After two years, Indiana student smokers smoked an average of 5.9 cigarettes, compared with 6.8 at Purdue. The percentage of Indiana students who said regulating smoking in public places is good increased to 82.1 percent, but decreased at Purdue to 81.5 percent. The percentage of Indiana students supporting a campus smoking ban increased by 5 percent, to 62.5 percent, while it dropped slightly at Purdue, to 61.3 percent.

“Although we haven’t pinpointed which element of the campus-wide smoke-free air policy contributed the most to the positive changes in students’ smoking rates, having such a policy in place does appear to influence students’ smoking-related norms and behaviors even without strong enforcement of the policy,” lead researcher Dong-Chul Seo of Indiana University said in a news release. “These results are encouraging for university administrators considering stronger tobacco control policies.”

The study appears in the journal Preventive Medicine.