How does soy protein quality compare with the quality of animal protein?

Soy protein is a high quality protein, equal in quality to meat, milk, and egg protein ⁹ . It has a Protein Digestibility Corrected Amino Acid Score (PDCAAS) of 1.0 - the highest score that a protein can have ⁹ . Soy protein meets or exceeds the essential amino acid requirements of both children over the age of two years and adults ¹⁰ , ¹¹ , and is highly digestible.