Question: how to calculate percentage of peak flow?
Answer: Children PEFR = ((Height in cm - 100) x 5) + 100.
Adult Men = (((Height in m x 5.48) + 1.58) - (Age x 0.041)) x 60.
Adult Women = (((Height in m x 3.72) + 2.24) - (Age x 0.03)) x 60.