PARENTS LESS AWARE WHEN THEIR KIDS VAPE.

Most parents know or suspect when their offspring smoke, but they are much more likely to be in the dark if a child vapes or uses other tobacco products, according to a study by researchers at the University of California, San Francisco.

The study, which tracked more than 23,000 participants aged 12 to 17 years old, found that parents or guardians were substantially less likely to report knowing or suspecting that their child had used tobacco if the child used only e-cigarettes, noncigarette combustible products, or smokeless tobacco, compared to smoking cigarettes or using multiple tobacco products.

The researchers also found that when parents set strong household rules about not using tobacco--applying to all residents--their children were less likely to start tobacco use. Just talking to kids about not smoking was far less effective.

"We know that tobacco-free homes are a key tool to help prevent smoking by kids," says senior author Benjamin Chaffee, associate professor at the School of Dentistry. "What studies haven't examined is how tobacco-free homes stack up against other approaches and how much tobacco-free home rules might help...