Repeated visual field screening in the aged.

During 1977 and 1978 visual screening was performed in 1511 persons born 1907-1921 and taking part in a population survey. 8.4 years later the visual field screening was repeated in 2039 eyes of 1038 persons. The rates of unsuccessful tests improved or remained unchanged. The incidence of non-glaucomatous visual field defects was 0.006/year. Thus repeated visual field screening of persons in their seventies was both feasible and fruitful.