Which of the following is NOT a pulmonary function test?

An ECG, or electrocardiogram, is a test that measures the electrical activity of the heart. It provides information about the heart’s rhythm, size, and any potential issues with blood flow. While important in assessing cardiovascular health, it is unrelated to lung function or respiratory mechanics and is therefore not classified as a pulmonary function test.

In contrast, Forced Vital Capacity (FVC), Peak Expiratory Flow (PEF), and Diffusion Capacity (DLCO) are all specific pulmonary function tests designed to evaluate lung capacity, airflow, and gas exchange capabilities, respectively. FVC measures the total amount of air that can be forcibly exhaled after taking a deep breath, PEF assesses the maximum speed of expiration, and DLCO evaluates how well oxygen and carbon dioxide are exchanged between the lungs and blood. Each of these tests provides valuable insights into the respiratory system's performance, highlighting their relevance in pulmonary function assessments.