This is a US-based project which "leading the first large-scale, national, longitudinal study of development in gender nonconforming, transgender, and gender variant youth . In addition to our primary goal of supporting the first major study of transgender children in the U.S., we are also conducting research about the origins of anti-transgender bias, and have plans for outreach projects in collaboration with some of our partner organizations" (quoting the website).
As many of you know, I'm not a parent and don't often read posts in this sub-forum (so, apologies if this has been discussed elsewhere!), but it seemed like the kind of study PPK parents or their friends might be interested in, and I'm all for promoting awareness about people and projects that are "trying to do good". fwiw I found the study via the gendermom blog and her How to be a girl podcast, which was linked to by the NYT's What are we reading? list.