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Television and computer use 'linked to lower GCSE grades'

1:00pm Friday 4th September 2015 content supplied byNHS Choices

Moods and feelings were measured for two weeks before the start of the study using the Moods and Feelings Questionnaire. Socioeconomic status was worked out using their home postcode and the Index of Multiple Deprivation.

GCSE results were obtained from the Department for Education National Pupil Database, and academic performance was calculated using a points system for grades.

The researchers looked for associations after adjusting for potential confounding factors, such as:

  • body mass index (BMI)
  • socioeconomic status
  • sex
  • the time of year the measurements were taken
  • which schools they attended

What were the basic results?

The analysis was based on 845 adolescents with complete academic performance and activity data.

Girls were found to have significantly less internet and computer game time than boys, and spent more time reading and doing homework. Girls also performed better academically.

The study found an additional hour of daily screen time was associated with 9.3 fewer GCSE points, equivalent to the difference between two grades.

An extra hour of reading or homework (non-screen) was associated with 23.1 more points, reported to be the equivalent of one whole extra GCSE. The amount of physical activity taken wasn't associated with academic performance.

These findings weren't influenced by other variables. However, screen time was still associated with poorer scores after adjusting for physical activity, sedentary behaviour, reading and homework. 

How did the researchers interpret the results?

The researchers concluded an extra hour a day of screen time at 14.5 years old is equivalent to around two fewer GCSE grades - for example, from a B grade to a D - at 16 years old.

It was suggested it may be important to find the right balance between screen time and time spent on other activities to improve academic performance. Encouraging more physical activity didn't seem to result in poorer academic performance.


This study assessed the associations between activity level, screen time, non-screen time and GCSE results in British adolescents.

The main finding was an extra hour of time spent watching television or on the computer was associated with lower grades at GCSE level.

An extra hour of reading or homework was associated with better performance. Screen time was still associated with poorer scores after adjusting for measured physical activity levels and reading or homework.

This study has taken a fair sample size from two regions in the UK. But about 15% of participants had incomplete data and weren't included in the analysis. We can't be sure whether their inclusion may have altered the results.

The researchers suggest those with missing data may have had better mood scores and were less deprived, which may limit how much their results might apply to all adolescents.

Some of the data, such as sleep and sedentary behaviour, was also self-reported. This means it's not possible to ensure the data was correct.

The researchers also acknowledge they weren't able to take into account that some screen time may have been for homework, revision or other educational purposes.

And as the study was carried out in 2005, the results may be less relevant to today's adolescents, who generally have wider access to screen-based technology.

Overall, this study is unable to prove screen time causes poor academic performance - but it has shown a possible link.

Parents and adolescents who are interested in achieving the best grades possible may benefit from spending more time on homework and reading instead of focusing on reducing screen time alone. 


"Just one hour of TV or internet use each night can damage a child's GCSE chances," says the Mail Online. Worrying headlines like this are being widely reported in the UK media based on the results of a 10-year-old study...

Links to Headlines

Just ONE HOUR of TV or internet use each night can damage a child's GCSE chances, experts warn. Mail Online, September 4 2015

Watching TV seriously harms GCSE results, says Cambridge University. The Telegraph, September 4 2015

Each hour schoolchildren spend watching television sees GCSE results fall by equivalent of two grades, says new research. The Independent, September 4 2015

Teenagers who watch screens in free time 'do worse in GCSEs'. The Guardian, September 4 2015

Extra screen time 'hits GCSE grades'. BBC News, September 4 2015

Too much screen time 'worsens exam grades'. The Express, September 3 2015

An extra hour of TV a day costs two grades at GCSE. The Times, September 4 2015 (subscription required)

Links to Science

Corder K, Atkin AJ, Bamber DJ et al. Revising on the run or studying on the sofa: prospective associations between physical activity, sedentary behaviour, and exam results in British adolescents. International Journal of Behavioral Nutrition and Physical Activity. Published online September 4 2015

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