Good near visual acuity is important in for completing near visual tasks at school and at work. There are currently no studies comparing visual acuity procedures in commercially available logMAR near acuity charts. The purpose of this study is to evaluate the near visual acuity scores of the Patti Pics and HOTV charts, two commercially available logMAR charts, against an ETDRS gold-standard chart, as well as the interocular, monocular and binocular visual acuities. Twenty-two subjects aged 6 and above who were able to identify letters and symbols on these charts were invited to participate in the study.
Repeated measures analysis of the uncorrected visual acuity scores without adjustments revealed that the subjects’ uncorrected visual acuity with the ETDRS chart when compared to the Patti Pics chart was better by -0.042 logMAR units (p =0.017), or about 2 letters. The difference was no longer statistically significant (p=0.052) after Bonferroni adjustment was applied to the data. When compared with HOTV chart, the ETDRS yielded similar results (p=0.111). The results demonstrated a statistically, but not clinically, significant difference in the visual acuity results.
When comparing the right eye to the left eye with repeated measures analysis, the right eye results were -0.016 logMAR units or almost one letter better (p= 0.017). When comparing the right eye to both eyes, the visual acuity score for both eyes was better by -0.023 logMAR units, or one letter better (p= 0.007). When comparing the left eye to both eyes, both eyes were better by -0.39 logMAR units, or nearly 2 letters better (p= 0.001). After Bonferroni adjustment, the difference between the right and left eyes approached statistical significance (p=0.05), and the difference between OD and both eyes remained statistically significant (p =0.020), and the difference between OS and both eyes remained statistically significant (p= 0.003). The difference between the inter-ocular, monocular, and binocular visual acuity was also statistically, but not clinically, significant.