Scientists Are Ready to Move Beyond ‘Screen Time’
All screens are not equal. Stanford’s Human Screenome Project promises to map people’s digital behaviors in far more complex ways.
Scientists have spent years, and millions of dollars, correlating screen time with all manner of negative effects on young people: depression, anxiety, obesity, academic achievement, ADHD, and even childhood developmental delays. Several have found significant links, but others have turned up inconsistent or even contradictory results, and literature reviews often struggle to extract clear takeaways from them.
The problem, according to the authors of an op-ed published in the journal Nature last week, is that “screen time” is a deeply flawed metric. To improve upon it, they’ve launched what they’re calling the Human Screenome Project. It’s a research program built on a new tracking platform called Screenomics that logs screenshots of participants’ devices every five seconds throughout the day. The platform, which the study authors developed at Stanford University and plan to make available to other researchers, is meant to provide a finer-grained understanding of not just how much people use screens, but when, why, and how they use them. For now, it works on Android smartphones, Macs, and PCs, though the researchers plan to expand it to more operating systems in the future.
While the name is a playful take on the Human Genome Project, the effort is serious and ambitious in its own right. The goal is to place the (often maligned) field of media effects studies on a more rigorous footing for the digital era. And it will require participants to grant researchers access to their lives on an unprecedented scale, which raises questions of privacy and data security. The hope is that it will lead to more specific, reliable recommendations as to which types of screen time are most harmful and which might be less harmful or even beneficial in moderation.
Studies that rely on “screen time” as a metric typically ask participants to self-report the number of hours they spent on electronic devices each day, said Thomas Robinson, professor of pediatrics and medicine at Stanford and a co-author of the paper. But self-reporting is unreliable. Perhaps more importantly, not all screen time is equal.
“One person’s hour of screen time is very different than another person’s,” Robinson said in a phone interview. “An hour of screen time now is different than an hour of screen time three hours from now. If you’re lumping it all together, we’re missing almost all the things that we think make those exposures important.”
To see the problem, consider four adolescents. The first spends three hours a night playing video games and chatting with fellow gamers on Discord. The second spends three hours browsing and posting on Facebook, Instagram, and TikTok. The third spends three hours passively watching Netflix and YouTube. The fourth never sits down with a device for longer than 20 minutes at a time but gets notifications on their phone every five minutes throughout the day and typically spends only a few seconds or minutes responding to each.
In a study that measures screen time, they might all report spending three hours per day on their devices. Yet their experiences of those devices would have little in common. One might feel more connected, another more isolated; one might grow more anxious, another more listless. No wonder studies find it hard to draw solid conclusions about screen time’s effects. That’s why the Screenomics platform is designed to give researchers into exactly what people are doing on which screen at what time and for how long.
Screen time can still be a useful proxy for certain narrower metrics, Robinson said, such as a person’s exposure to blue light or their total exposure to advertising. “But in general, you’re missing the content — what people see, the actions they take — that are thought to be responsible for all of the cancerous effects of social media and also for the potential benefits.”
That doesn’t mean parents should stop worrying about their kids’ media exposure altogether. For all the shortcomings in the literature, more studies have found worrisome links between screen time and health outcomes than the opposite. But it means that limiting screen time alone is likely to be less effective in improving kids’ well-being than limiting specific types of screen time. As the op-ed’s authors put it in a post on The Conversation: “A media solution based only on screen time is like medical advice to someone taking multiple prescription medications to reduce their total number of pills by half. Which medications and when?”
The authors acknowledged that logging screenshots of research subjects’ devices every five seconds is highly invasive and comes with risks. While the project is just beginning, they’ve already collected more than 30 million screenshots from some 600 voluntary participants in the United States, China, and Myanmar, who consented after being fully informed of what data will be collected. Byron Reeves, a co-author and professor of communication at Stanford, told the MIT Technology Review that with such deep access to people’s online lives, it can be tempting to “watch voyeuristically.”
But they argue it’s better for academics to collect such data themselves, through processes vetted by institutional review boards, than to rely solely on self-reporting or to partner with tech platforms that have vested interests in flattering research outcomes. “We go to extreme lengths to protect the data, and we promise never to share it,” Robinson said. He noted that human genome research is invasive, too — but the scientific payoffs, like early detection of hereditary conditions and drugs tailored to genetics, can be worth it.