Zeiss Humphrey II-i series, User Manual

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Test Reliability
Humphrey Field Analyzer II-
i
series User Manual 2660021145640 A
6-6
False Negative Errors
Occasionally during a test, a stimulus is repeated at a particular location and at a level much
brighter than has already been seen. If the patient does not respond to this trial stimulus, a false
negative error is recorded. A high false negative score may indicate a fatigued patient, inattentive
patient, or a malingerer, but it is also commonly seen in reliable patients who have genuine
significant visual field loss.
The HFA screen will display the total number of false negative errors followed by the total number of
trials. On the printout, SITA Standard and SITA Fast test results will display False Negative results as
percentages. Because the SITA strategies analyze the data at the end of the test before displaying
final values, use the False Negative value printed with the results if the displayed and printed out
values differ.
Additional information pertaining to the Full Threshold and FastPac testing strategies can be found
in
Appendix (L) .