ANT	The 1-D lung length at the anterior chest wall margin
CNT	The 1-D lung length at the (central) tracheal bifurcation point
CSA	Cross-sectional area
DIA	Diaphragm length
DMD	Duchenne Muscular Dystrophy
FVC	Forced vital capacity
LOA	Loss of ambulation
MEP	Maximal expiratory pressure
MIP	Maximal inspiratory pressure
MRI	Magnetic Resonance Imaging
PCF	Peak cough flow
PEF	Peak expiratory flow
PST	The 1-D lung length at the posterior chest wall margin
%Pred	FVC as percentage of predicted normal values
R	Correlation coefficient of the linear regression
S	Slope of the linear regression
TDM	Total distance of motion of the diaphragm