bsi.RdBoundary Shift Integral Summaries (Nick Fox's lab)
data(bsi)
A data frame with 3602 rows and 20 variables
A dataset with variables as follows:
RID N Participant roster ID
SITEID N Site ID
VISCODE T Visit code
USERDATE S Date record created
RECNO N
EXAMDATE D Examination Date
IMAGEUID N imageUID
FLDSTRENG N Field Strength
BBSI N ml Boundary Shift Integral from baseline
DBCBBSI N ml Differential Bias Corrected Boundary Shift Integral from baseline
VBSI N Ventricular BSI
BRAINVOL N ml Segmented brain volume. Not to be used as a measure of intracranial volume.
VENTVOL N ml Segmented ventricular volume
REGCOMMENT T
REGRATING N
VENTACCEPT N A boolean to indicate whether or not we have confidence in the VBSI value. Similar purpose to the REGRATING.
KMNDBCBBSI N An improved version of the Differential Bias Corrected Boundary Shift Integral from baseline, which: a) Has a new intensity normalisation step that normalises scan intensity by matching the intensities by tissue type (cerebrospinal fluid, grey matter, white mater) instead of being just based on the average whole brain intensity. This helps reduce artefactual change in the BSI that might be caused by change in contrasts between scans (e.g scanner changes) b) Automatically calculates the BSI window based on k-means clustering of tissue intensities for each scan pair
KMNREGCOMMENT T
KMNREGRATING N