Peak flow monitoring in children.

Home monitoring of peak expiratory flow (PEF) has become an integral part of asthma management in adults, with the practice being extended into the paediatric age group. However, there have been no systematic studies investigating the advisability of this practice in managing childhood asthma. Recent studies have questioned the accuracy of mini-PEF meters in the paediatric group, and have demonstrated that the relationship between change in PEF and change in lung function may be poor. Furthermore, symptoms of asthma frequently precede changes in PEF, limiting the ability of PEF monitoring to "predict" the onset of asthma episodes. These data question the routine use of PEF monitoring in the management of childhood asthma, and suggest that the decision to institute home PEF monitoring should be made by an experienced clinician on an individual basis.