The fragile foundation of a study on “anti-transgender” laws and youth suicide is crumbling

In 2024, the journal Nature Human Behaviour published an article that quickly made headlines in numerous media outlets. It claimed that restrictive state laws regarding gender had increased suicide attempts among transgender and non-binary youth by up to 72%. The message was clear: policies driven primarily by Republican-controlled legislatures were causing direct and measurable harm to these young people’s mental health.

According to an exhaustive analysis published by City Journal, center-left media outlets such as NPR, The Washington Post, CNN, Time and Scientific American, among others, reported the news with an emphasis on causality. The study’s authors themselves reinforced this interpretation. The first, Wilson Lee, posted on LinkedIn: "In this study, we presented causal evidence that enacting state-level anti-transgender legislation increased suicide attempts among transgender and nonbinary young people in the US."

Co-author Ronita Nath told CNN that this was the first demonstration of a causal relationship between "anti-transgender" policies and worse health outcomes among LGBTQ+ youth.

However, a little over a year later, a methodological critique published in the same journal debunked much of those conclusions. The case illustrates recurring problems in some of the scientific literature on gender: biased samples, weak designs and a tendency to draw strong causal claims from fragile data.

Problems with the data

The researchers, all affiliated with the Trevor Project (an advocacy organization for suicide prevention among LGBTQ+ youth), used the group’s own surveys conducted between 2018 and 2022. This is a convenience sample recruited through social media: 35,196 children and young people aged 13 to 24. This type of non-probability survey is prone to self-selection bias.

According to City Journal, participants in the Trevor Project survey were likely motivated to provide the answers the organization expected.

"And because the survey was taken against the backdrop of 'anti-transgender' laws passing around the country—and a constant drumbeat of alarm about those laws—it’s at least possible that some respondents were motivated to exaggerate or misrepresent their experiences of suicide attempts."

Examples of similar surveys, such as the 2015 U.S. Transgender Survey, have revealed issues with retrospective memory and misinterpretation of questions (for example, confusing puberty blockers with adult hormone therapy). It is not unreasonable to think that a media environment saturated with warnings about "anti-transgender" laws could affect how participants respond.

Furthermore, the study included a broad spectrum of LGBTQ+ youth, not just those seeking medical transition interventions. Mixing these groups makes it difficult to isolate the specific effect of restrictions on hormonal or surgical treatments.

"By including data from kids who identify as transgender but do not seek medical transition (a larger group than those seeking medical interventions), we risk 'contaminating' the sample, as those kids may have different psychological response mechanisms."

Methodological Flaws

According to City Journal, the study’s most serious problems lie in its methodology. The authors based their causal claims on a method called Difference-in-Differences (DiD), which compares changes between groups before and after an intervention. However, this approach fails in several key respects.

First, they treated 48 state laws as if they were all the same under the label "anti-transgender." Of these, 30 regulated sports (banning biological males from women’s categories) and only seven set age limits for hormone treatments. Assuming that all of them have the same psychological impact on LGBTQ+ youth is highly questionable.

Second, the DiD method requires that the groups being compared follow parallel trends prior to the laws. This condition was not met: Idaho, where the alleged effect was concentrated, had specific health restrictions due to COVID-19 that could have affected mental health. The control variable used (COVID-19 deaths) is inadequate, since young people rarely died from the virus but did suffer significant psychological impacts from the pandemic.

Third, the “effect” found is extremely weak: no widespread increase was observed. The entire alleged significant increase in subsequent periods was limited to approximately 100 young people in Idaho, and the laws in that state were not even in effect (they had been blocked by the courts more than a year earlier).

In response to these criticisms, the authors stated that “the public discourse surrounding the passage of these laws would not have ceased when they were enjoined, providing a further plausible mechanism for sustained effects.”

This admission is revealing. Methodological critics cite in this context an important article by Alison Clayton from 2023: “An excessive focus on an exaggerated suicide risk narrative by clinicians and the media may create a damaging nocebo effect (e.g., a 'self-fulfilling prophecy' effect) whereby suicidality in these vulnerable youths may be further exacerbated."

Conflicts of interest, bias and activist agenda

In this study, all authors were affiliated with the Trevor Project, an organization whose fundraising, according to City Journal, depends directly on maintaining the perception of a serious suicide crisis among LGBTQ+ youth. Although they disclosed this affiliation, many readers are unaware of the financial incentive this represents.

Furthermore, the authors claim that “gender-affirming healthcare has well-established benefits,” but they cite only opinion polls and the standards of the World Professional Association for Transgender Health (WPATH). They fail to mention the compelling evidence that the WPATH suppressed systematic reviews after discovering disappointing results. Furthermore, they ignored systematic reviews concluding that there is no credible evidence of mental health benefits for minors.

According to City Journal, the most striking aspect is the open confession by one of the co-authors in an interview with CNN: "We knew if we were able to show this it would be a breakthrough for using definitive scientific evidence to support calls for protective and affirming policies for trans and nonbinary young people and to help, ultimately, save their lives." This statement reveals that the study was designed from the outset as a tool for political advocacy rather than neutral research.