Visual Acuity and Self-Reported Visual Function among Migrant Farmworkers

Visual impairment presents significant risks for occupational injuries among farmworkers, a vulnerable population with limited access to vision care. Although previous research has noted farmworkers' low lifetime experience with vision screening and high rates of complaints of eye ailments and poor vision, there have been few screening data collected to evaluate these self-reports. The objectives of this analysis are to (1) describe farmworker visual health using standardized visual acuity screening data and self-reported visual function, and (2) to compare the screening and self-report data.

Data are from a cross-sectional study of eye health among Latino migrant farmworkers in North Carolina with uncorrected vision (n = 289). Workers were recruited using methods to achieve a representative sample of a hard-to-reach population. Visual acuity data were collected using Snellen Tumbling E charts for nearsightedness and farsightedness. Binocular data are reported here. Interviews were conducted to obtain personal characteristics and self-assessed visual function.

About 75% of farmworkers reported never having had a vision screening. Based on binocular screening, 1.7% (distance vision) and 6.9% (near vision) had moderate to severe visual impairment (>20/40). Farmworkers self-reported poorer visual function, compared with screening results; only 36.4% reported good or very good vision. Sensitivity of distance and near vision self-reports were 60 and 20%, respectively, but specificity was high.

This study confirms past reports of little vision screening among farmworkers. Visual impairment for distance is comparable to other studies of Latinos in the US, though these studies have not reported near vision. Self-reports of vision problems are not a sensitive measure of visual acuity among farmworkers. Screening is needed to identify visual impairment that can create occupational safety risks in this health disparate population.