Data
286,819 items of data are available, covering 236,313 participants.
Defined-instances run from 0 to 3, labelled using Instancing
2.
Average compound dataset is 771b, largest is 842b.
4 Instances
Instance 0 : Initial assessment visit (2006-2010) at which participants were recruited and consent given
170,565 participants, 170,565 items
Data not meaningful for statistical summary
Instance 1 : First repeat assessment visit (2012-13)
20,208 participants, 20,208 items
Data not meaningful for statistical summary
Instance 2 : Imaging visit (2014+)
84,010 participants, 84,010 items
Data not meaningful for statistical summary
Instance 3 : First repeat imaging visit (2019+)
12,036 participants, 12,036 items
Data not meaningful for statistical summary
Notes
Wave data containing 3 waveforms, each consisting of one direct and one reflected component.
A digital volume pulse can be considered to be the summation of a direct and a reflected component. The direct component is due to transmission of a pressure wave from the left ventricle to the finger via the most direct route. The reflected component is formed by pressure transmitted from the heart to the lower body where it is reflected back up the aorta and thence to the finger. Each waveform is actually a single pulse with 100 points. Since the heart rate is in beats per minute, a single beat takes 60seconds / Heart Rate and time between two beats is (60/Heart Rate)/100.
The data is formatted as follows:
- The first number (i.e. digits before the first '|' character)indicate the number of points X,Y for the curve.
- Each pair of X,Y values is separated by a '|' character from the preceding/succeeding pair.
- Each pair of X,Y values is separated internally by a ',' character.
The X-axis is the time in milliseconds and the Y-axis is the Pulse signal strength in arbitrary units.