Why is averaging the reading of the peak expiratory rate not recommended?

Averaging the readings of peak expiratory flow (PEF) is not recommended because it can mask significant fluctuations in a patient's respiratory function. PEF can vary considerably throughout the day and under different conditions, so averaging may obscure acute changes that indicate worsening Asthma or other respiratory conditions. Instead, monitoring should focus on the highest and lowest values to accurately assess variability and ensure timely intervention. Additionally, individual day-to-day comparisons are more informative for managing respiratory health.