Purchase this article with an account.
J.L. Keltner, C.A. Johnson, K.E. Cello, J. Fan, R.A. Levine, S.E. Bandermann, M.A. Kass, M.O. Gordon, R.W. Beck, Ocular Hypertension Treatment Study Group; Visual Field Quality Control in the Ocular Hypertension Treatment Study (OHTS) and the Optic Neuritis Treatment Trial (ONTT) . Invest. Ophthalmol. Vis. Sci. 2006;47(13):3394.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To compare visual field quality control (QC) data in the Ocular Hypertension Treatment Study (OHTS) and in the 10–year Optic Neuritis Treatment Trial (ONTT) follow–up study.
We evaluated 46,777 visual fields from 1,618 OHTS participants and 722 visual fields from 270 ONTT participants. The visual field QC protocol in OHTS included training, certification, and on–going feedback to technicians on each visual field as well as quarterly reports on visual field quality. The visual field QC protocol in ONTT included training and certification, but lacked on–going feedback on each visual field and repeated visual field testing of participants over time. An ancillary study was also conducted in the ONTT using the SITA (Swedish Interactive Thresholding Algorithm) Fast Central 24–2 test strategy. Five clinical centers participated in this ancillary study.
For OHTS, 2.4% (1,136 of 46,777) of the visual fields were unreliable and 0.23% (107 of 46,777) had incorrect test parameters. For the ONTT 10–year follow up study, 6% (43/ 722) of the visual fields were unreliable and 19% (134/722) had incorrect test parameters. Visual field defects attributed to testing artifacts contributed to approximately 1% (483/ 46,777) of the OHTS total visual fields and 1% (7/722) of the ONTT total visual fields. There were 6 major QC differences between study parameters used in OHTS and ONTT which included different visual field entry, shipping and testing requirements, certification procedures, QC reporting, and error notification.
Reliability was high in both studies. Ongoing quality control, along with technician feedback/instruction, helps to reduce unreliability and incorrect test parameters in visual field data.
This PDF is available to Subscribers Only