(In 1951, Dr. Haas published "The Management of Celiac Disease", a book that describes using the specific carbohydrate diet to treat celiac disease. At the time, the SCD was a well-known standard treatment for celiac disease.)
Recently, I was trying to learn about the decline in the use of Haas's diet after the celiac disease/gluten connection was discovered. I ran across a 1969 cookbook titled "Cooking for your Celiac Child". The introduction of this recipe book describes using a strict "beginning diet" for children with severe symptoms:
The next paragraph then describes an SCD-like diet: "meats, fish, gelatin desserts, bananas, homemade broths and simple soups . . . cooked fruits and vegetables and non-processed cheeses such as pot cheese, natural Swiss, and cheddar."
This description appears to show a transition period in treating celiac diesease: where the SCD and a gluten-free diet were both in use.