In upper airway obstruction, all of the following changes are seen except
Decreased maximum breathing capacity
RV decreased
Decreased FEV
Decreased vital capacity
Changes in lung function tests in obstructive lung diseases- Eg: Emphysema
TLC- Increase
RV- Increase
FRC- Increase
Peak expiratory flow rate- Decrease
FEV1- Decreased out of proportion to FVC (Forced vital capacity)
Forced expiratory vital capacity (FEVC)- Normal to slightly decreased
FEV1/FEVC- Decreased (May decrease as low as 20-30%)
 Changes in lung function tests in restrictive lung diseases
TLC- Decreased
RV- Decreased
FRC- Decreased
Forced mid-expiratory flow rate- Decrease
FEV1- Decreased in proportion to FVC (Forced vital capacity)
Forced vital capacity (FVC)- Decreased 
FEV1/FEVC- Near-normal or increased.
Lung compliance- decreased
Diffusion capacity- decreased