To the Editor.—Thank you for referring Dr. John Hyde's letter to us.
In regard to the first point made, we agree that any pulmonary function measures must be related to weight, height, age, and sex, with the possible exception of the midexpiratory time. However, our graph was merely included to illustrate the message in the text that objective measurements, such as the peak expiratory flow rate assist in the management of severe perennial asthma in children. The intent was to illustrate that a change downward from a control level was a warning to reassess the therapy and thus avoid catastrophic asthmatic episodes. For this purpose, we felt that addition of the other data was superfluous.
The second point raised was in regard to the use of peak expiratory flow rate measures in an outpatient context. We have no quarrel with the indications set forth by Dr. Hyde, but