Poor sleep in early childhood can lead to a whole host of difficulties later down the line, including health problems, developmental difficulties, and behavioural issues. This is because the time the brain spends in sleep mode is essential for building connections based on experiences throughout the day – it's how all the new information babies, toddlers and young children come across is embedded for future use. Without good, solid sleep, these connections are stymied or prevented.

In recent years, various screen-based items have been integrated into our daily lives, with young children particularly affected by their normalisation. Some of the downsides of this are well noted, including the influx of children who try to do things such as ‘zoom in’ on book text or turn book pages with a flick of their finger. Yet, one element that has been widely discussed while remaining purely speculation is the effect screen time – especially prior to bedtime – can have on the growing brains of little ones.

A group of researchers from a range of universities and a number of early years organisations came together to discover once and for all the impact screen time can have on the sleep of little ones, conducting research with over a hundred families – and we’ve got the summary below.

The Bedtime Boost study, funded by the Nuffield Foundation, is the first randomised controlled trial (RCT) supporting paediatric guidance to limit toddler screen time before bed.

Researchers from University of the Arts London (UAL), Birkbeck, Queen Mary University of London, University of Bath, and King’s College London recruited families with 16 to 30-month-old toddlers from across London.

105 families who already used screens with their child before bed were randomly allocated to either the intervention group or one of two control groups, with 35 families in each group.

In the intervention group, parents were asked to remove all screen time in the hour before bed and use a Bedtime Box containing non-screen-based activities instead (e.g. calming play, reading or puzzles) over a seven-week period.

Parents in the intervention group were able to successfully remove toddlers’ screen time before bed, and toddlers’ sleep quality improved, with more efficient nighttime sleep and fewer night awakenings.

Families in the two control conditions were either told to continue with their typical bedtime routine or asked to do similar activities from the Bedtime Box. Neither control group was told anything about screen time. Toddler sleep in all groups was recorded before and after the intervention period using a wearable motion tracker.

The study stated: “The mechanism(s) by which before-bed screen time may negatively impact toddler sleep are not fully understood, but our preliminary results suggest that it may be due to the screen use itself, rather than displaced activities, as the Bedtime Box only encouraged the same before-bed activities as PASTI.”

Professor Rachael Bedford, Head of the Queen Mary Child Development Lab and co-lead on the project, said: “We worked closely with parents and early years practitioners to ensure the Bedtime Boost intervention was low-cost and easy to implement. Results suggest the trial was highly feasible for parents, with all of the intervention families completing the trial. However, further work is needed to understand how the varied ways in which families use screen media may influence these effects.”

Further information on the discoveries in the study – and how it can be both extended and improved upon in future – can be found in the final research paper: bit.ly/PASTI-research-doc.

The intervention was co-created with families and early-years experts, including representatives from the Early Years Alliance, National Childbirth Trust, The Sleep Charity, and children’s centre staff, to ensure the intervention was as inclusive as possible.