“There're new names on a lot of these publications,” said Ted Alcorn, an instructor at Columbia who analyzed gun-related science publications over the past few decades.

Jordan Orange, a pediatric immunologist at Columbia University, was not involved in the St. Jude study but helped develop a gene therapy for another immunodeficiency disease called Wiskott-Aldrich.

The parent training seems to work because it lets children confront their anxieties, says Anne Marie Albano, a psychologist at Columbia University.