The FDA has issued final guidance for manufacturers of infant formula and laboratories conducting testing on infant formula.
The guidance was developed to help manufacturers and laboratories in the design, conduct, evaluation, and reporting of Protein Efficiency Ratio (PER) studies. Protein is an essential nutrient to support growth and development in infants. In its announcement about the guidance the Food and Drug Administration said PER studies are used to assure the quality of the protein in the infant formula, which is often a sole source of nutrition for infants.
Guidance documents do not carry the weight of law, but are suggestions for industry. It usually takes years for guidance documents to be proposed and approved.