There’s little evidence that the amount of time teenagers spend in front of a screen — even before bedtime — affects their psychological well-being, according to a new multicountry study from British researchers.

If there is any effect, it is minuscule when compared to other activities in an adolescent’s life, the study’s authors say.

This research calls into question claims that the more time young people spend online, gaming or watching TV, the greater their risk of depression and anxiety.

The authors of the study, which was published Friday in the journal Psychological Science, say those claims are based on studies whose findings were never clear-cut and whose methodology had significant flaws.

“Psychological science can be a powerful tool for quantifying the association between screen use and adolescent well-being, yet it routinely fails to supply the robust, objective, and replicable evidence necessary to support its hypotheses,” write the study’s coauthors, psychologists Andrew Przybylski and Amy Orben of the University of Oxford.

“As the influence of psychological science on policy and public opinion increases, so must our standards of evidence,” they add.

How the study was done

For their study, Przybylski and Orben analyzed data collected between 2011 and 2017 in three earlier studies that took place in Ireland, the United States and the United Kingdom. The data came from more than 17,000 12- to 15-year-olds, and involved not just the young people’s self-reports of their screen time, but also data from time-tracking diaries that they filled in at regular intervals during their waking hours.

As Przybylski and Orben point out, most other studies that have looked at the effects of digital technology on teens have relied only on self-reports, which are unreliable. In fact, research has found that only about a third of people give accurate accounts when asked how much time they spend online.

Heavy users of digital media tend to underestimate their screen time, and intermittent users tend to overestimate it.

In addition, Przybylski and Orben used a research approach called preregistration, which is considered a more robust way of testing hypotheses. They created a public document of how they were going to analyze the data before they reviewed it.

As explained in a press release about the study, that process “prevents hypothesizing after the results are known, a challenge for controversial research topics.”

What the study found

Przybylski and Orben hypothesized that they would find a correlation between the total time teenagers spent “engaging with a digital screen” and their psychological well-being. Instead, however, their analysis revealed that screen time had little impact on the teens’ mental health, either during the school week or on weekends.

In fact, the effect was so small that teens “would need to report 63 [hours] and 31 [minutes] more of technology use a day in their time-use diaries to decrease their well-being by 0.50 standard deviations” — an amount considered large enough for the teens to notice, the researchers write.

The study also found that spending time in front of a screen before bedtime had no effect on young people’s well-being, “even though this is a well-worn idea both in the media and in public debates,” Przybylski and Orben point out.

Staying skeptical

Although its methodology may have been more robust than that used in previous research, the current study is not without its own limitations. To begin with, time-use diaries may be more accurate than self-reports of technology use, but they are not entirely reliable, either.

In addition, the data used to measure the teens’ well-being in the study were not collected on the same day as the time-use-diary data, a factor that may have hidden a day-to-day negative correlation between mood and screen use.

It’s also important to note that this study looked only at the amount of time teens spend with digital media. It did not examine whether digital content — what teens look at when online — has any impact on their psychological health.

Nor is mental health the only reason limiting screen time is a good idea. The less time young people spend texting or on Instagram or Snapchat, the more time they have to be physically active, finish their schoolwork and get a good night’s sleep.

Still, this study underscores why it’s a good idea to retain some level of skepticism when evaluating psychological research — about teens’ screen time or anything else.

As Przbylski and Orben write, “To retain the influence and trust we often take for granted as a psychological research community, robust and transparent research practices will need to become the norm — not the exception.”

FMI: You can download and read the study in full at Psychological Science’s website. The journal is published by the Association for Psychological Science.