A survey of parents finds those with children in hybrid learning programs that combine in-person and virtual school are more likely to say they started or increased using substances to help cope with stress or emotions during the COVID-19 pandemic, CNBC reports.

The Centers for Disease Control and Prevention surveyed parents or guardians of school-age children up to age 12 between October and November. Almost half of parents reported increased levels of stress. The survey found 16.5% of parents said they had started or increased their use of substances, including alcohol, legal or illegal drugs, or prescription drugs that are taken in a way not recommended by the doctor.

Among parents whose children went to school only in person, 13.7% reported new or increased substance use, compared with 16.4% virtual only, and 20.5% combined in-person and virtual schooling.

“The pandemic is disrupting many school-based services, increasing parental responsibilities and stress, and potentially affecting long-term health outcomes for parents and children alike,” lead author Jorge Verlenden said.