Family Nurse Practitioner Exam

Which factors are NOT used to determine Peak Expiratory Flow (PEF)?

1. Age

2. Gender

3. Height

4. Weight

The correct answer is: Weight

Peak Expiratory Flow (PEF) is a measure used to evaluate the maximum speed of expiration, which is commonly used in assessing conditions like asthma. The calculation of PEF is influenced by several physiological factors, primarily age, gender, and height. Age is crucial because lung function tends to change as people grow and age. Generally, PEF values are established based on normative data that account for these age-related changes. Similarly, gender plays a significant role since men typically have larger lung volumes compared to women, affecting PEF readings. Height is another factor since taller individuals usually have larger lung capacities, which correlates with higher PEF values. Weight, while it can influence overall physical health and fitness, is not a direct factor in calculating PEF. Instead, it is the structural and biological characteristics of the individual, as determined by age, gender, and height, that serve as the primary determinants for establishing a normal PEF range. Thus, weight does not play a role in determining PEF, making it the correct answer in this context.