A method of determining ageing effect and cardiovascular risk in a human patient comprising: - (i) measuring the arterial pulse waveform of the patient when the heart is beating regularly, (ii) extracting the frequency dependent components of the pulse waveform, (iii) determining the ratio of the amplitude based value of the first harmonic (H1) to the amplitude based value of a selected higher harmonic to provide an index of arterial ageing, and (iv) Comparing the index to normative values of index of arterial ageing to determine ageing effect and cardiovascular risk. Other methods of calculating the index based on harmonic amplitudes and the phase angle are also disclosed and claimed.