Protein efficiency ratio is -
Protein efficiency ratio (PER) is based on the weight gain of a test subject divided by its intake of a paicular food protein during the test period. From 1919, until very recently, the PET has been a widely used method for evaluating the quality of protein in food Ref: Dictionary of public Health, Dr. Jugal Kishore Pgno : 423-424
Gain weight per unit of protein consumed
Product of digestibility coefficient and biological value divided by 100
Percentage of nitrogen retained out of the nitrogen absorbed
Percentage of protein absorbed after digestion
Nutrition and health