Dr. Raphael David research studies focused on the complexities of adrenal gland steroidogenesis, with specific attention on congenital adrenal hyperplasia as well as Sertoli and Leydig cell function. His research has furthered understanding of adrenal disorders, aldosterone deficiency, Sertoli and Leydig cell maturation, growth and pubertal disorders, as well as thyroid disease in children. As founder of the steroid laboratory at Bellevue at a time that rapid hormonal assays were not readily available for infants, he saved countless newborns born with congenital adrenal hyperplasia by diagnosing patients in the first days of life, assuring that life-sustaining treatment could be immediately instituted.