Abbreviation	Definition	Equation
IMT	Intima Media Thickness
SBP	Systolic blood pressure
DBP	Diastolic blood pressure
d	Diameter of the carotid artery end-diastole
Δd	The change in diameter from diastole to systole
p	Pulse pressure in branchial artery
Δp	The difference between systolic and diastolic blood pressure	SBP-DBP
DC	Distensibility coefficient	DC = (2 × d × Δd + Δd2)/(d2 × Δp)
CC	Compliance coefficient	CC = π (2 × d × Δd + Δd2)/(4 × Δp)
E	Young’s elasticity modulus	E = d/(IMT × DC)
β	Stiffness Index β	β = d × ln (SBP/DBP)/Δd
cPWV	Local carotid pulse wave velocity	1/√ (ρ × DC) (ρ = blood density = 1060 kg/m3)