Stockiness is a relative comparison of a player character's BMI to that of another player character or mob. By using the consider command, a player will be given one of three messages, each of which is based on the difference between the BMI of the player and the target in question.
If (Player_BMI - Target_BMI) > 0.1, "less stocky than you"
If (Player_BMI - Target_BMI) < -0.1, "stockier than you"
If -0.1 < (Player_BMI - Target_BMI) < 0.1, "about as stocky as you"
-  - WoTMUD Archives forum posting on BMI testing