Final answer:
The claim is false; a 5% deviation in lung volumes from predicted values does not necessarily suggest pulmonary disease. Spirometric measures, particularly the FEV1/FVC ratio, are critical in diagnosing conditions like asthma and lung fibrosis.
Step-by-step explanation:
The statement that pulmonary disease is suggested when lung volumes deviate from predicted values by 5% or more is false. Lung volumes and capacities can vary due to a host of factors and do not necessarily indicate disease with minor discrepancies. However, significant changes in lung function, such as those measured by spirometry, can indicate pulmonary conditions. Spirometry measures the forced expiratory volume (FEV1) and the forced vital capacity (FVC). The FEV1/FVC ratio is particularly important in diagnosing diseases like asthma, emphysema, and fibrosis. A high FEV1/FVC ratio may indicate lung fibrosis, where the lungs become stiff and less pliable. Conversely, a low ratio could indicate diseases like asthma, where there is increased resistance in the airways making exhalation difficult.