Data
85,451 bulk items are available, covering 79,129 participants.
Defined-instances run from 2 to 3, labelled using Instancing
2.
The values held within this field are coded links to files held within a bulk repository, not the actual data itself.
2 Instances
Instance 2 : Imaging visit (2014+)
78,838 participants, 78,838 items
Data not meaningful for statistical summary
Instance 3 : First repeat imaging visit (2019+)
6,613 participants, 6,613 items
Data not meaningful for statistical summary
Notes
This field contains image files from the carotid ultrasound imaging.
These images are provided in .mat file format.
Each .mat file contains the following: - CI_F - A 3-dimensional matrix of single precision values representing a 2-dimensional image through time.
- FrameNum - The number of frames.
- HP - Various meta-data describing the acquisition of the ultrasound image.
- Xhv and Yhv: These variables may assist with coordinating plotting the image data. The values are calculated from the size of display area and sampling pitch. The image data at Fr frame: CI_F(Frame, i, j). Plot the value of CI_F(Fr, i, j) at the coordinate (Xhv(i), Yhv(j)).
Data have not been preprocessed and therefore, temporal and spatial filtering may be required to optimally utilise the images. UK Biobank cannot currently provide guidance on the best approach for these filterings.
Images in the original .Cine format, other images, and meta-data from the measurement device can be found in field 20241.
2 Related Data-Fields
Field ID | Description | Relationship |
20241 | Raw carotid device data | Current Field is derived from Field 20241 |
30029 | Reason cine file not available | Field 30029 explains why there is no value for Current Field |