published the seminal study Notes from a Different Drummer (1977), followed by More Notes from a Different Drummer (1984). Today, disability in juvenile literature is a standard topic included in bibliographies, research, criticism, and review sources. Several bibliographies and studies reviewing fiction and non-fiction have been produced in the years since. The evolution of the portrayal of disability can be seen in the books written since the 1970s. Judy Blume shows the experience of a teenage girl diagnosed with idiopathic scoliosis in Deenie (1973). The protagonist, Deenie, faces the challenges brought by having to wear a body brace during her treatment, which impacts her perceptions of herself and those of her family and fellow students. Deenie does not overcome the disability by the end of the story, nor is she defeated by it; the conclusion more realistically shows her continuing to face challenges and learning to adjust to them. A trend in current juvenile fiction is the portrayal of characters with "hidden disabilities" that have become more common diagnoses in recent decades. Examples include Petra Mathers' Sophie and Lou, about extreme shyness that is an emotional and social disability, and Caroline Janover's The Worst Speller in Jr. High (1995) about a boy with dyslexia. In fiction for older youth, disability has recently been dealt with in complex situations with nuanced techniques such as multiple-perspective narrative; an example is Erika Tamar's Fair Game (1993), about a group of male students who repeatedly sexually assault an intellectually disabled girl at their school. Bibliographer Debra Robertson, who wrote Portraying Persons with Disabilities: An Annotated Bibliography of Fiction for Children and Teenagers (1992), pointed out in the early 1990s that not every disability has to be a "metaphor for a protagonist's development", and the tendency of writers to romanticize or stigmatize medical conditions in this way is a persistent problem in juvenile literature. More recent studies have indicated that educators may improve student understanding of disability with "follow-up discussion or activities and stories that portray characters with disabilities accurately, realistically, and positively". Researchers from the University of Prešov completed a research project focused on human disadvantage in book production for children and young people (original and translated literature from the mid-19th century to 2020). The results showed the historical variability of literary and artistic creative approaches to depicting the topic. Every two years, the International Board on Books for Young People (IBBY) published a