Reason Roundup

CDC Inflated Data About Teen Girls and Sexual Assault

Plus: Lack of independence could cause childhood mental health issues, Biden follows Trump playbook on TikTok, and more...


The Centers for Disease Control and Prevention (CDC) inflated data about teen girls and sexual assault in a news release about a new CDC report on teenage mental health. In 2021, the percentage of teen girls who reported that they had ever been "forced to have sex" was up 27 percent since 2019, the health agency said, calling it "the first increase since the CDC began monitoring this measure."

The percentage of teen girls reporting this in the CDC's Youth Risk Behavior Survey reporting did rise, unfortunately—but not by quite the magnitude that the CDC news release said, reports Washington Post fact checker Glenn Kessler. The actual increase was not 27 percent, but 18.4 percent.

And even this number leaves some room for doubt, owing to differences in data collection between previous-year surveys and 2021.

"The CDC's focus on the challenges facing teenage girls — especially regarding mental health — is timely and important. But the CDC's use of inflated figures on sexual violence could undermine its larger message," suggests Kessler.

The first problem with the CDC's data stems from rounding. In 2019, 11.4 percent of teen girls in the Youth Risk Behavior Survey said they had been forced to have sex; in the 2021 survey, it was 13.5 percent. That's a rise of 2.1 percentage points or—put another way—an 18.4 percent increase. In presenting the data, however, the CDC rounded the 2019 number down to 11 percent and the 2021 number up to 14 percent. Using these rounded numbers, you get a 27 percent increase.

Any increase here is concerning, of course. And whether it's 11 or 14 percent, that's still a disturbingly large percentage of teen girls who say they've been forced to have sex.

But some experts suggest that CDC data inflate a rise in recent years, since a lot of schools surveyed refused to ask students questions about sexual violence.

The increase in the number of schools choosing not to ask that question is huge. In 2017, 4 percent of schools surveyed didn't ask their students about any sexual violence and 2 percent didn't ask about rape, according to mathematician David Stein. In 2019, a quarter of schools surveyed failed to ask questions about any sexual violence and 18 percent didn't ask about rape. In 2021, 23 percent didn't ask about sexual violence and, again, 18 percent didn't ask about rape.

"That could have biased the sample by possibly removing jurisdictions with lower rates of reporting rape and sexual violence," Kessler points out:

Stein's analysis of the available 2019 data suggests girls who were not given the questions were considerably younger than those who had received the questions and thus less likely to have had sex and to be sexually active — two factors, he said, that are associated with a higher risk of being a victim of sexual violence.

Elizabeth L. Jeglic, a clinical psychologist who studies sexual violence prevention at John Jay College in New York, said she could not comment specifically on the CDC methodology, but she said sampling and response rate can affect findings. "If the question is asked about lifetime occurrence and younger girls are not being sampled (or less likely to be sampled) you will likely see a higher prevalence rate as older girls will have more years to experience sexual violence than younger girls," she said in an email.

Kessler notes that "other survey questions with more robust participation by schools — such as violence in dating and violence in bullying — indicated declines, not increases."

For instance, the National Crime Victimization Survey suggests teen rates of experiencing sexual assault and rape have declined over the past three decades. And the CDC's Adolescent Behaviors and Experiences Survey (ABES) puts the rape victimization rate at 10.4 percent and the sexual violence victimization rate at 15.3 percent.

Kessler also noticed that the 2019 to 2021 rise was not actually the first increase. The rate also went up between 2001 and 2003 (from 10.3 to 11.9), between 2009 and 2011 (from 10.5 to 11.8), and between 2015 and 2017 (from 10.3 to 11.4).

"The recently released report provides insight on the changes that occur from the beginning to the end of the time period (in this case, 2011 to 2021)," CDC spokesperson Paul Fulton Jr. told Kessler in a statement. "CDC began monitoring the 10 year trends in the 2017 [Youth Risk Behavior Survey Data Summary & Trends Report] …In that report and again for 2019 (2009-2019) there were no significant increases in forced sex across those time periods."

Full data from the Youth Risk Behavior Survey will not be published until April. The data we have currently come from the CDC's "Youth Risk Behavior Survey Data Summary & Trends Report: 2011-2021" report.

Sexual violence against teen girls is certainly a problem worth attention. But addressing the problem requires accurate knowledge about what's working and what isn't, and part of that means getting an accurate picture of whether sexual violence is increasing or decreasing and by how much. The CDC doesn't do teens any favors by inaccurately representing the data.


Could lack of independence explain teen mental health problems? For social psychologist and pundit Jonathan Haidt (and many, many others), declines in teen mental health measures are primarily a function of social media and too much time in front of screens. And perhaps because this theory fits so nicely into so many preexisting political narratives and plays into longstanding fears of new technology, you'll actually be hard-pressed to find many people who will challenge it. But a group of professors writing in The Journal of Pediatrics offer an alternative explanation: A decline in independent activity is causing a decline in young people's mental well-being.

"Our thesis is that a primary cause of the rise in mental disorders is a decline over decades in opportunities for children and teens to play, roam, and engage in other activities independent of direct oversight and control by adults," they write.

Economist Emily Oster calls it "extremely hard to be fully convincing in this case," but finds "the data they talk about interesting" and offers a summary here. "It seems hard to argue with the conclusion that, relative to the 1980s, children have less physical freedom," she writes. But "if we acknowledge that independence has gone down, making the link to happiness would require knowing those factors are related," and "the evidence here is a lot more indirect":

The authors link their ideas to theories about locus of control. It has been widely demonstrated that having low levels of internal locus of control — basically, feeling that you do not have a lot of control over your own life — leads to higher levels of depression and anxiety. Feelings of internal locus of control have declined over time. The authors hypothesize that independence at younger ages, with the associated need to problem-solve, could contribute to higher levels of internal locus of control. By extension, the loss of this time may contribute to the decline in these levels. This fits, but requires us to stretch beyond the data in the link between independence and these feelings.

A second theoretical link is with self-determination theory, which suggests that people are happier if they feel like they are living in accordance with their own desires, rather than being driven from the outside. The authors again hypothesize — although this isn't something we see directly in data — that independence might play a role in increasing these feelings of self-determination.

A final point relates to our evolutionary background. For most of human history, and still in many societies today, children had more freedom (and more was expected of them in terms of contribution to the larger group). The common setup we have today, with the combination of scaffolding and expectation, is counter to this. So perhaps kids are not adapted to it. (I'd recommend Hunt, Gather, Parent for a different type of perspective on this.)

More here.


Biden follows Trump playbook on TikTok. Like the Trump administration did previously, "the Biden administration wants TikTok's Chinese ownership to sell the app or face a possible ban," reports The New York Times:

The new demand to sell the app was delivered to TikTok in recent weeks, two people with knowledge of the matter said. TikTok is owned by the Chinese internet company ByteDance.

The move is a significant shift in the Biden administration's position toward TikTok, which has been under scrutiny over fears that Beijing could request Americans' data from the app. The White House had been trying to negotiate an agreement with TikTok that would apply new safeguards to its data and eliminate a need for ByteDance to sell its shares in the app.

But the demand for a sale — coupled with the White House's support for legislation that would allow it to ban TikTok in the United States — hardens the administration's approach. It harks back to the position of former President Donald J. Trump, who threatened to ban TikTok unless it was sold to an American company.

TikTok said it was weighing its options and was disappointed by the decision. The company said its security proposal, which involves storing Americans' data in the United States, offered the best protection for users.

Chris Stokel-Walker, the author of TikTok Boom: China's Dynamite App and the Superpower Race for Social Media, weighed in this week on a potential TikTok ban, calling it an "entirely un-American, undemocratic and inappropriate response to an unproven risk that the Chinese-owned platform will share users' data with Beijing for nefarious purposes."

"TikTok's U.S. executives have repeatedly denied that they have been pressed by the Chinese government to share data and say they would refuse to do so if the request ever came," notes Stokel-Walker:

Reporters, including me, have tried for years to prove these executives are not telling the truth but have turned up nothing. Current and former TikTok staff members have dished plenty of dirt on the company to me, but no one has ever confirmed a great data transfer.

Of course, even if ByteDance hasn't handed over data, who's to say it wouldn't in the future? But is that any different for any number of social media companies, many of whom have extensive, valuable operations in China? Meta, the company behind Facebook and Instagram, was recently fined for mishandling user data under European Union rules.

Meanwhile, TikTok is bending over backward to assuage fears. Project Texas involves a U.S. subsidiary that would control U.S. user data and answer directly to the Committee on Foreign Investment in the United States, while its European equivalent, Project Clover, would do something similar in Europe.

Reason has previously published a lot about why fears of TikTok as a national security threat are overblown and a ban is unworkable, unwise, and authoritarian, so I'll leave you with some of those:


• Takeaways from yesterday's federal court hearing on a lawsuit seeking to ban abortion-inducing drugs.

• "Texas officials on Wednesday announced a state takeover of Houston's nearly 200,000-student public school district, the eighth-largest in the country, acting on years of threats and angering Democrats who assailed the move as political," reports NBC News.

• The U.S. maternal death rate continued its recent rise in 2021. Some 1,205 women died in childbirth or from related causes, up from 658 deaths in 2018, 754 in 2019, and 861 in 2020.

• Writer Freddie deBoer attempts a thorough (but critical) definition of woke politics.

• "Most of the nation's major cities face a daunting future as middle-class taxpayers join an exodus to the suburbs, opting to work remotely as they exit downtowns marred by empty offices, vacant retail space and a deteriorating tax base," writes Thomas B. Edsall in The New York Times.

• Some reasons to be skeptical about President Joe Biden's story of him and his father witnessing two men kiss on the streets in the early 1960s.

• ChatGPT may have a political bias problem.

• The city of Newark, New Jersey, "was about to become a Sister City with a Hindu nation, but there was one problem -- the nation doesn't exist," reports CBS News.