Parents are less likely to suspect when their kids vape or use other tobacco products than they are when they smoke cigarettes, a new study finds.

About 70% of the parents and guardians of children who smoke reported being aware or suspecting it. For kids who use e-cigarettes, the percentage is about 40%, the study said.

“When parents think about tobacco, many will picture smoking a cigarette but other tobacco and nicotine products may not come to mind,” said Dr. Benjamin Chaffee, a senior author of the study and associate professor at University of California San Francisco School of Dentistry.

Get the full story at cnn.com.