- Watching TV seriously harms GCSE results, says Cambridge University - The Telegraph
- Each hour schoolchildren spend watching television sees GCSE results fall by equivalent of two grades, says new research - The Independent
- An extra hour of TV a day costs two grades at GCSE - The Times
- Teenagers who watch screens in free time 'do worse in GCSEs' - The Guardian
- Extra screen time 'hits GCSE grades' - BBC
The majority of articles took the research findings at face value - watching TV results in lower exam grades, and assumed a cause and effect; the common mistake of assuming that a correlation is a causation. Just because there is a relationship between two things (correlation) does not mean that the two are related (causation) - one may not be the specific cause of the other.
A good explanation of the dangers of mistaking correlation for causation, and a related example can be found in the excellent Freakonomics book, by Stephen J. Dubner and Steven D. Levitt. This identified a study that highlighted that children got better exam results if their homes had more books. Whilst there is a connection, its not likely to be causal - the existence of many books is likely to be an indicator of the interests of the parents, and therefore highlight the parenting style and approach. Upbringing and parenting is much more likely to have a causal effect. One district took the flawed approach of responding to the original study by sending two books to all homes with children; assuming this would 'fix' the problem.
The same problem applies to this current news coverage (though the research itself was carried out in 2005-2007, so it's age may reduce its relevancy - much has changed in the last decade); as the headlines assume that the amount of TV watched is the cause of exam pass-rate variation. There is very limited coverage as to the extent to which the two are connected, even though the researchers had some awareness of the risk:
The BBC quoted lead author Dr Kirsten Corder: "We followed these students over time so we can be relatively confident of our results and we can cautiously infer that TV viewing may lead to lower GCSE results but we certainly can't be certain. Further research is needed to confirm this effect conclusively, but parents who are concerned about their child's GCSE grade might consider limiting his or her screen time." Dr Corder suggested there could be various reasons for the link, including "substitution of television for other healthier behaviours or behaviours better for academic performance, or perhaps some cognitive mechanisms in the brain".
This is further backed up by detail in the research paper:
Our analyses are prospective therefore allowing cautious inferences about direction of association; however it would be impossible to tell whether reductions in screen time caused an increase in academic performance without a randomised controlled trial.
There are clearly a wide range in potential factors in upbringing that could have influenced the results. For example the research adjusted for 'deprivation' by using a post-code based scoring indicator. But as the authors indicate more work needs to be done, to provide a greater depth of analysis.
'Screen-time', whether TC, Internet or games is clearly a factor to be balanced in children's free time, few would argue that it should argue that it should have limits. Whilst the news headlines seem to over emphasise the relationship, it would be interesting how many readers have some shift in behaviour in the current weeks as their children head back to school, or if their underlying parenting style, modified from their own upbringing has most ongoing impact.
And if you're still not convinced by the risk of mistaking correlation vs causation, then take a look at this site of 'Spurious Correlations' my favorite being: the year-on-year correlation between the 'Number of Japanese Cars sold in the US' and the level of 'Suicides by crashing of motor vehicle'.
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