Lily Curran (far right), who is transgender, plays with a group of friends, some of whom are also trans.Barcroft Media / Getty Images

Since 2013, Kristina Olson, a psychologist at the University of Washington, has been running a large, long-term study to track the health and well-being of transgender children—those who identify as a different gender from the one they were assigned at birth. Since the study’s launch, Olson has also heard from the parents of gender-nonconforming kids, who consistently defy gender stereotypes but have not socially transitioned. They might include boys who like wearing dresses or girls who play with trucks, but who have not, for example, changed the pronouns they use. Those parents asked whether their children could participate in the study. Olson agreed.

After a while, she realized that she had inadvertently recruited a sizable group of 85 gender-nonconforming participants, ages 3 to 12. And as she kept in touch with the families over the years, she learned that some of those children eventually transitioned. “Enough of them were doing it that we had this unique opportunity to look back at our data to see whether the kids who went on to transition were different to those who didn’t,” Olson says.

By studying the 85 gender-nonconforming children she recruited, her team has now shown, in two separate ways, that those who go on to transition do so because they already have a strong sense of their identity.

This is a topic for which long-term data are scarce. And as transgender identities have gained more social acceptance, more parents are faced with questions about whether and how to support their young gender-nonconforming children.

“There’s a lot of public writing focused on the idea that we have no idea which of these gender-nonconforming kids will or will not eventually identify as trans,” says Olson. And if only small proportions do, as some studies have suggested, the argument goes that “they shouldn’t be transitioning.” She disputes that idea. “Our study suggests that it’s not random,” she says. “We can’t say this kid will be trans and this one won’t be, but it’s not that we have no idea!”

“This study provides further credence to guidance that practitioners and other professionals should affirm—rather than question—a child’s assertion of their gender, particularly for those who more strongly identify with their gender,” says Russell Toomey from the University of Arizona, who studies LGBTQ youth and is himself transgender.

(A brief note on terms, since there’s a lot of confusion about them: Some people think that kids who show any kind of gender nonconformity are transgender, while others equate the term with medical treatments such as hormone blockers or reassignment surgeries. Neither definition is right, and medical interventions aren’t even in the cards for young children of the age Olson studied. That’s why, in her study, she uses pronouns as the centerpiece marker of a social transition. Changing them is a significant statement of identity and is often accompanied by a change in hairstyle, clothing, and even names.)

When the 85 gender-nonconforming children first enrolled in Olson’s study, her team administered a series of five tests that asked what toys and clothes they preferred; whether they preferred hanging out with girls or boys; how similar they felt to girls or boys; and which genders they felt they currently were or would be. Together, these markers of identity gave the team a way to quantify each kid’s sense of gender.

The team, including James Rae, now at the University of Massachusetts Amherst, found that children who showed stronger gender nonconformity at this point were more likely to socially transition. So, for example, assigned boys who had the most extreme feminine identities were most likely to be living as girls two years later. This link couldn’t be explained by other factors, such as how liberal the children’s parents were. Instead, the children’s gender identity predicted their social transitions. “I think this wouldn’t surprise parents of trans kids, and my findings are often ‘duh’ findings for them,” says Olson. “It seems pretty intuitive.”

Charlotte Tate, a psychologist from San Francisco State University, says that this quantitative research supports what she and other transgender scholars have long noted through qualitative work: There really is something distinctive and different about the kids who eventually go on to transition. From interviews with trans people, “one of the most consistent themes is that at some early point, sometimes as early as age 3 to 5, there’s this feeling that the individual is part of another gender group,” Tate says. When told that they’re part of their assigned gender, “they’ll say, ‘No, that’s not right. That doesn’t fit me.’ They have self-knowledge that’s private and that they’re trying to communicate.”

Olson’s team also showed that those differences in gender identity are the cause of social transitions—and not, as some have suggested, their consequence. After assessing the group of 85 gender-nonconforming children, the team administered the same five tests of gender identity to a different group of 84 transgender children who had already transitioned, and to a third group of 85 cisgender children, who identify with the sex they were assigned to at birth. None of these three groups differed in the average strength of their identities and preferences. In other words, trans girls who are still living as boys identify as girls just as strongly as trans girls who have transitioned to living as girls, and as cis girls who have always lived as girls. Put another way: Being treated as a girl doesn’t make a trans child feel or act more like a girl, because she might have always felt like that.

“Implicit in a lot of people’s concerns about social transition is this idea that it changes the kids in some way, and that making this decision is going to necessarily put a kid on a particular path,” says Olson. “This suggests otherwise.” Children change their gender because of their identities; they don’t change their identities because they change their gender.

“The findings of this compelling study provide further evidence that decisions to socially transition are driven by a child’s understanding of their own gender,” says Toomey. “This is critically important information given that recent public debates and flawed empirical studies erroneously implicate ‘pushy’ parents, peers, or other sources, like social media, in the rising prevalence of children and adolescents who identify as transgender.”

Olson’s new findings come on the back of another controversial study, from 2013, in which Thomas Steensma from University Medical Center in Amsterdam studied 127 adolescents who had been referred to a clinic for “gender dysphoria”—a medical term describing the distress when someone’s gender identity doesn’t match the gender assigned at birth. Only four people in that cohort had socially transitioned in early childhood, and all of them ended up identifying as transgender. By contrast, most of those who had not transitioned did not have gender dysphoria later.

“People have taken from that study that a lot of these kids are not going to be trans adults so you shouldn’t be socially transitioning them, or that social transitions are changing kids’ identities,” Olson says. But “we’re suggesting that the kids who are socially transitioning seem to be different even before that transition, which shifts the interpretation of that past study.” (Steensma did not respond to requests for comment.)

Olson admits that there are weaknesses in her new study. It’s relatively small, and all the children came from wealthy, educated, and disproportionately white families. And since it began almost by accident, when parents of gender-nonconforming children approached her, she couldn’t preregister her research plans, a growing practice in psychology. (It reduces the temptation to fiddle with one’s methods until they yield positive results and instills confidence among other scientists.)

To at least partly address these shortcomings, Olson did a multiverse analysis: She reran her analyses in many different ways to see whether she still got the same result. What if, instead of using all five tests of gender identity, she just looked at combinations of four? Or three? Two? The team ran all these what-if scenarios, and in almost all of them, the results were the same. “They went above and beyond the analyses typically conducted and presented in scientific journals,” says Toomey. “Their results were robust across these additional tests, suggesting that readers can have a high level of confidence in these findings.”

Olson stresses that she has no magic test that can predict exactly which children will transition and which will not. It’s a question of probabilities. In her study, based on their answers, all the children got a gender-nonconformity score between 0 and 1. For comparison, those who scored 0.5 had a one-in-three chance of socially transitioning, while those who scored 0.75 had a one-in-two chance.

“How much gender nonconformity is ‘enough’ to allay the anxieties parents feel around transition is an open question,” says Tey Meadow, a sociologist from Columbia University who studies sexuality and gender and has written for The Atlantic. Parents are the ultimate arbiters of a child’s access to transition, and they make decisions “in a culture that encourages parents to look for every possible alternative to transness,” Meadow adds.

“It's not like you can take a blood sample or do an MRI,” says Aaron Devor, the University of Victoria’s chair of transgender studies, who is himself transgender. “One of the phrases often used is ‘consistent, persistent, and insistent.’ When you get that constellation, that kid is also a kid who might want to transition. And that’s what [Olson’s] research is corroborating. It adds some very valuable data.”

Devor and others note that Olson’s earlier studies suggest that children who are supported and affirmed in their transitions are just as mentally healthy as cisgender peers. That reminds him of seminal work by the American psychologist Evelyn Hooker. In the 1950s, when many psychologists saw homosexuality as a mental illness (largely because they had only ever worked with gay people who had records of arrest or mental-health problems), Hooker surveyed a more representative sample and found that gay and straight men don’t differ in their mental health. That was instrumental in getting homosexuality removed from a list of mental-health disorders in 1987. “We’re sitting in a similar moment today with transgenderism,” says Devor. “The mental-health issues that we see are largely the result of living a life that blocks your expression of your gender. My view is that the work coming out of Olson’s group will have an Evelyn Hooker effect.”

I am reminded of what Robyn Kanner wrote in The Atlantic last year: “Society has done nothing for trans youth for so many years. People have to trust that the youth who sway in the breeze of gender will land on their feet when they’re ready. Wherever that is, it’ll be beautiful.”

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