Australian parents with multiple children often struggle to ensure their kids meet screen time guidelines, research has revealed.

A University of Queensland study has found slightly more than half of families kept to the guidelines when their children were in the same age-based screen time category.

However, Associate Professor Leigh Tooth from the School of Public Health said, in stark contrast, only 23% of families with children in different aged-based screen time categories were adhering to the recommendations.

"We also found toddlers exceeded guidelines by matching the screen time of their older siblings, in a national study of 1,993 mothers and 4,543 children aged under 12," Dr. Tooth said.

"And, in a sub-sample of children aged two to four years who had siblings in different aged-based screen time categories, many exceeded guidelines by up to 92%."

In Australia, and other countries, screen time guidelines are based on age.

The current recommendations are no screen time for children younger than 2, one hour per day for those aged two to four years, and two hours per day for kids between five and 12 years of age.

Dr. Tooth said these guidelines failed to account for the reality of parenting multiple children of different ages.

"While many guidelines now focus on quality over quantity, such as co-viewing and enriching content, difficulties remain for families with several children," she said.

"We would like to see current screen time guidelines modified to accommodate families with multiple children and more policies and resources with practical tips and strategies for parents.

"Screen time guidelines, like those for physical activity, nutrition and sleep, are an important guide for parents to help children develop a healthy balance across their daily activities and reduce the risk of developing a chronic disease in the future."

Data used in this study was taken from the Australian Longitudinal Study on Women's Health (ALSWH) and Mothers and their Children's Health (MatCH) sub-study involving families with three children under 13 years old.

The ALSWH acknowledges the Australian Government Department of Health for funding and the women who provided the survey data.

The paper is published in JAMA Pediatrics.