SWEDISH INTERACTIVE THRESHOLD ALGORITHM (SITA)
SITA is a family of testing strategies that measure threshold sensitivity and reliability parameters efficiently, thereby achieving
optimal measurements in minimal time.
STATPAC
STATPAC is a trademark for Humphrey software that performs a
series of statistical calculations on visual field test results. Displays
include single-field analysis, Guided Progression Analysis (GPA),
change analysis, and overview.
GUIDED PROGRESSION ANALYSIS (GPA)
GPA is a new approach to detecting progression events and trends
that spans several platforms including the Humphrey Field Analyzer
(HFA) and Cirrus HD-OCT (both products from Carl Zeiss Meditec,
Inc., Dublin, CA). On the HFA, the event-based GPA identifies statistically
significant progression. Two visual fields are required to establish
a baseline examination. GPA flags points exceeding expected
patient variability and employs strict progression criteria from the
Early Manifest Glaucoma Trial.
VISUAL FIELD INDEX
The Visual Field Index (VFI) is a perimetric staging index that is designed to be less affected by cataracts. VFI is expressed as a
percentage, where 100% represents a normal visual field and 0% represents a perimetrically blind field.
VFI PLOT
The VFI Plot applies linear regression analysis to series of test results to help identify patients who are progressing at rapid
rates. The VFI Plot can be found in the new GPA of the HFA.
