Study: Kids’ Bedtimes May Impact their Test Scores

“Set bedtimes can lead to cleverer children,” the Daily Express reports, while BBC News and others report that late nights “sap children’s brain power”. But looking at the study these headlines are based on, it appears that most of these claims are misleading.

Essential Sleep Habits for KidsThe news comes from a large UK study looking at whether regular bedtimes affect children’s reading, maths and spatial ability scores at age seven.

The study found that irregular bedtimes at age three were independently associated with slightly lower cognitive scores at age seven. It also found that in all three tests, girls (but not boys) who had irregular bedtimes at age seven had slightly lower scores than those with regular bedtimes.

The researchers suggest that disrupted sleep patterns may hamper kids’ concentration, and that lack of sleep may disrupt the brain’s ability to learn.

However, regularity of bedtimes is hard to measure and may be caused by underlying factors, such as a chaotic family life, which may contribute towards lower cognitive functioning.

While the researchers attempted to adjust for these factors (known as confounders), this is unlikely to have completely removed their influence.

Is your child a problem sleeper?

If you regularly have problems getting your child to sleep, it’s worth reading about some of the common sleep problems in children.

Exhausted parents may also find these healthy sleep tips useful.

Where did the story come from?

The study was carried out by researchers from University College London and was funded by the Economic and Social Research Council.

It was published in the peer-reviewed Journal of Epidemiology and Community Health.

As might be expected, the study was widely covered in the media, with some reports stressing the advantages of set bedtimes. For example, ITV News claimed regular bedtimes could “boost brain power”, a headline that is not supported by this study’s findings.

The results actually suggest that irregular bedtimes may disrupt the normal pattern of child development – set bedtimes neither “boost” nor disrupt “brain power”.

And while most news reports were basically fair, some of the claims overinterpreted the study’s results. Researchers tested the children’s maths, reading and spatial ability only once. While important, this is hardly a reliable measure of how clever the children were, or of the “power” of their brains.

What kind of research was this?

This was a large cohort study of more than 11,000 seven year olds in the UK. It looked at whether there were any links between regular bedtimes in early childhood and cognitive test scores at age seven.

A cohort study enables researchers to follow large groups of people for lengthy periods, and to study any associations between lifestyle (such as bedtimes) and a particular outcome (such as cognitive test scores). However, on its own it cannot prove a direct cause and effect relationship (causality).

The researchers say that in childhood, reduced or disrupted sleep at key times of development could have an important impact on health throughout life. But most research into sleep and cognitive function has been done in adults and adolescents.

The researchers also say that busy family lives and full-time employment could leave parents and carers feeling as if they do not have enough time with their children. This means there could be an increasing number of parents or carers who delay bedtimes or do not stick to a routine.

What did the research involve?

The researchers used a sample of children from the Millennium Cohort Study. This is an ongoing nationally representative cohort study looking at health outcomes in children who were born in the UK between 2000 and 2001.

Families were visited at home when the children were aged nine months, and three, five and seven years old. During these visits, parents were asked a range of questions about socioeconomic circumstances and family routines.

When the children were aged three, five and seven, their mothers were asked whether they always, usually, sometimes or never went to bed at a regular time on weekdays and during term time. Information about bedtimes at weekends was not collected by the researchers. For five and seven-year-olds with regular bedtimes, researchers also asked what time they went to bed.

At age seven, trained interviewers carried out cognitive assessments of the children. Using established tests, the interviewers assessed three aspects of cognitive performance – reading, maths and spatial ability (the capacity to think about objects in two or three dimensions, such as using a map to navigate).

The researchers conducted two analyses:

  • Whether the time a child goes to bed and the consistency of his or her routine was associated with performance in tests at the same age (a cross-sectional analysis)
  • Whether there was any association between test performance at seven and bedtimes at the earlier ages of three and five – this was to see if there was any “cumulative effect” of bedtime on cognitive ability, or if there were “sensitive periods” during early childhood where bedtime is more critical, for example, if a disruption of bedtime routine in early childhood leads to future problems

The researchers created various models to take account of confounders that might influence the results of the study, including:

  • Child’s age
  • Mother’s age
  • Family income
  • Educational qualifications of parents
  • Mother’s psychological health
  • Methods of discipline
  • Daily activities
  • Hours spent watching TV or using a computer

The researchers used three types of statistical model:

  • Model A, which adjusted the results for the child’s age
  • Model B, which adjusted for factors known to have an effect on cognitive development, such as parental education or whether parents read to or tell their child stories daily
  • Model C, which adjusted the results for factors known to effect quantity and quality of sleep, such as whether a child has a TV in their bedroom

What were the basic results?

The researchers found that irregular bedtimes were most common at age three. At this age, around one in five children went to bed at varying times. By age seven, more than half the children went to bed regularly between 7.30 and 8.30pm.

  • At age seven, girls who did not have a regular bedtime performed worse than those who did in tests for reading, maths and spatial ability. This result was found in all three statistical models. The same association was not found in boys of the same age.
  • Irregular bedtimes at age three were independently associated with lower reading, maths and spatial ability scores at age seven in both girls and boys.
  • Girls who never had regular bedtimes at ages three, five and seven had significantly lower reading, maths and spatial scores at seven years than girls who did have regular bedtimes. For boys, this was the case for those with irregular bedtimes at any two of the ages.

The researchers found that children who had irregular or later bedtimes tended to come from more socially disadvantaged backgrounds. They were also more likely to have mothers with poor mental health and have more unfavourable routines, such as skipping breakfast or having a TV in the bedroom. However, time pressures, parental employment and whether parents felt they spent enough time with their child were not associated with later or inconsistent bedtimes.

How did the researchers interpret the results?

The researchers suggest that inconsistent bedtime schedules might affect cognitive development by disrupting circadian rhythms or by affecting the brain’s “plasticity” – the ability to acquire and retain information.

They also suggest that the effect is cumulative and that age three could be a sensitive period where cognitive development is affected by late or inconsistent bedtimes. They say girls might be more susceptible to irregular bedtimes than boys.

They also suggest that inconsistent bedtimes during childhood could have knock-on effects throughout life.

They add that policies are needed to better support families to “provide conditions in which young children can flourish”.


This was a large nationally representative sample of children who were followed for several years, so the results are more likely to be reliable than small, short studies.

Getting regular sleep is important for children’s health, and children require more sleep than adults, so it is not surprising that children going to bed late at age seven also perform worse in mental tests.

Of concern, too, is the suggestion that irregular bedtimes at earlier ages might affect children’s mental performance at the age of seven.

However, it should be noted that the study has the following limitations:

  • Children were only tested for cognitive ability once
  • Not having a regular bedtime at three was associated with only a small difference in test scores at seven
  • It is possible that other factors, such as social deprivation, affected test scores, although the authors tried to take these into account
  • The study relied on parental recall of bedtimes, which might affect the reliability of the reported data
  • As the authors point out, direct data on the children’s actual sleep quantity and quality was not available – a study recording this could have led to more accurate results

Bedtime routines are important for children. Anyone who has persistent problems getting young children to bed should talk to their GP.

Read more about common sleep problems in children.

Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter.


“Set bedtimes can lead to cleverer children,” the Daily Express reports, while BBC News and others report that late nights “sap children’s brain power”. But looking at the study these headlines are based on, it appears that most of these claims are overstated.

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Child Health & Safety News Roundup: 12-21-2015 to 12-27-2015

twitter thumbIn this week’s Children’s Health News: Succeeding at School With Fibromyalgia

Welcome to Pediatric Safety’s weekly “Child Health & Safety News Roundup”- a recap of the past week’s child health and safety news headlines from around the world. Each day we use Twitter and Facebook to communicate relevant and timely health and safety information to the parents, medical professionals and other caregivers who follow us. Occasionally we may miss something, but we think overall we’re doing a pretty good job of keeping you informed. But for our friends and colleagues not on Twitter or FB (or who are but may have missed something), we offer you a recap of the past week’s top 15 events & stories.

PedSafe Child Health & Safety Headline of the Week:
Many new parents misuse car seats, endangering babies – CBS News

Milestones for Parents of Special Needs Children

special needs mom watches childFrom the moment a baby is born, new parents (not to mention pediatricians) tend to obsess about milestones. Rolling over, sitting up, babbling, first steps are not only signs of your child’s development they also feel like validation that you are doing your parenting job correctly. But sometimes when you have a special needs baby these milestones don’t happen on schedule – sometimes they may not happen at all. Of course it has nothing to do with your parenting, but many times it is impossible to avoid feeling like you failed as a parent, especially when the other parents around you are gushing with pride over their typical baby’s milestones and accomplishments. So as we get ready to ring in a New Year, I suggest we continue to celebrate every inch of progress our special needs children make in their own time, and also become aware of the milestones we reach as special needs parents.

The first time I left my baby home with daddy so I could go to the grocery store I was a wreck! And that was one of my typical babies! Now that they are older I walk out of the house without a second thought – milestone! I used to stand ready to jump in with every task for my special needs child. Now I see that she needs to be independent, even if that means sweeping up and throwing out half a box of Cheerios (again). I have to let her try, even if she is only partially successful. Milestone!

I don’t know what the milestones look like for you, but take a moment to appreciate your development as a special needs parent. You might just be amazed at how far you have come!

The Other Gifts We Give Our Kids

Christmas dayThere are many traditions at this time of year that involve parents giving their children presents – whether obviously or through Santa subterfuge! But there are many gifts we give our kids throughout the year that have a much more lasting impact than the latest hot video game or toy, even if our little people don’t yet realize it or always appreciate our efforts. Below is a selection of some of these gifts of love.


The WHO cites a book on the history of vaccination that says only clean water has done more for the health and wellness of mankind. Historical books, movies and TV shows detail just how frightening the diseases we vaccinate against once were. The shots we get for our children are a gift that provides a lifetime of protection – for them and those around us.

Safe Home

Every time parents install a cabinet lock to hide chemical cleaners, secure heavy furniture and TVs against tipping, or reduce the setting of their water heater they are providing invaluable gifts to their children – reduction in the risk of preventable poisoning, injury, burns. The Consumer Product
Safety Commission
says that 22,000 kids are seen in Emergency Departments each year due to injuries from furniture and TV tip-overs – and 26 kids die annually from these incidents.

Safe Transport

Around 400-500 child deaths are prevented in the US every year due to use of car seats and other child restraints – and that’s not counting the reduction in severe injuries from use of safety seats for kids. Every time we strap them into a car seat we are giving them a precious gift and teaching them good car safety habits for when they become drivers.

Healthy Eating Appreciation

Obesity is one of the greatest health crises of our age, given its link to diabetes, heart disease, high blood pressure and cholesterol, liver disease, sleep apnea, arthritis, and even several cancers. Helping our children appreciate food for its support of health is a gift that keeps giving over a lifetime.

Active Lifestyle Encouragement

As parents, we all want our children to live a long and happy life. Physical activity is a important contributor to this goal, given how it reduces risk for chronic diseases and even improves mental health, sleep and mood.

According to the US Centers for Disease Control, “only a few lifestyle choices have as large an impact on your health as physical activity. People who are physically active for about 7 hours a week have a 40 percent lower risk of dying early than those who are active for less than 30 minutes a week.”

Getting our kids to be active – and, more importantly, being a role model for physical activity is literally a gift of life.

Protection from Excessive/Inappropriate Online Exposure

Although the American Academy of Pediatrics has updated their guidelines for “screen time” to better reflect how entrenched online usage now is at all ages, they still make recommendations – such as focusing on content and engaging with your kids around screens – to ensure a valuable online experience. Putting limits in place for when our kids can access the internet and what they can see is an important gift for protecting their online reputation and preventing inappropriate connections.

So while you are savoring your kids squeals of delight when they open their presents during the holidays, remember to pat yourself on the back for all the other gifts you labor to give them year-round – gifts that protect them for a lifetime.

Video: Stairs, Water & More – Preventing Child Accidents at Home

Katrina Phillips of the Child Accident Prevention Trust explains how to make your home childproof and prevent avoidable accidents.

Editor’s Note: Video Highlights

There are hazards all around the home. This video covers the following key accident risks and areas of the house:

  • Stairs – barriers are needed at the top and bottom of stairs to protect young children – and toys at the top of stairs can be a risk for all family members
  • Bathrooms
    • Don’t leave cleaners under the sink or by the side of the toilet or bath – even if they have “childproof” caps – many 3-year olds can open these containers
    • Scalding bath water is a major hazard – always make sure the water is the right temperature before filling the bath

Note: In the UK, generally hot and cold water run through separate taps – so the advice in the video is UK-specific. In North America, the usual advice for bath water is to get the water running to the right temperature before filling it for your child – and to reduce the temperature of your hot water heater to avoid accidental scalding.

  • Bedrooms
    • Little girl playing with household cleanersIf your window can fully open, invest in window locks to prevent falls
    • Beware of window blind cords – young children can get wrapped in these and strangled
  • Kitchen
    • It’s important to keep pot handles and electric leads or cords away from edges of counters and small hands
    • Also ensure your cabinets have childproof locks – especially if they contain cleaners
  • Family Room or Lounge
    • Beware of hot cups of coffee or tea – Did you know a baby’s skin is 15 times thinner than an adult’s? – so hot liquid can do them much greater harm
  • Transportation Safety
    • Car seats are critical for kids – but ensure you have the correct seat for your child’s age and weight
    • Ensure your child always uses a helmet with a bike – even if just around your yard / driveway
    • Check out the video for more safe biking tips for your child – a healthy way to get around

Child Health & Safety News Roundup: 12-14-2015 to 12-20-2015

twitter thumbIn this week’s Children’s Safety News: F.D.A. Proposes Ban on Indoor Tanning for Minors to Fight Skin Cancer

Welcome to Pediatric Safety’s weekly “Child Health & Safety News Roundup”- a recap of the past week’s child health and safety news headlines from around the world. Each day we use Twitter and Facebook to communicate relevant and timely health and safety information to the parents, medical professionals and other caregivers who follow us. Occasionally we may miss something, but we think overall we’re doing a pretty good job of keeping you informed. But for our friends and colleagues not on Twitter or FB (or who are but may have missed something), we offer you a recap of the past week’s top 15 events & stories.

PedSafe Child Health & Safety Headline of the Week:
Was Everyone Invited But Me? Helping Teenagers Deal with FOMO (Fear of Missing Out)