Reading charts in ophthalmology

Abstract

A new generation of logarithmic reading charts has sparked interest in standardized reading performance analyses. Such reading charts have been developed according to the standards of the International Council of Ophthalmology. The print size progression in these calibrated charts is in accordance with the mathematical background of EN ISO 8596. These reading charts are: the Bailey-Lovie Word Reading Chart, the Colenbrander English Continuous Text Near Vision Cards, the Oculus Reading Probe II, the MNREAD Charts, the SKread Charts, and the RADNER Reading Charts. The test items used for these reading charts differ among the charts and are standardized to various extents. The Bailey-Lovie Charts, MNREAD Charts, SKread Charts, and RADNER Charts are also meant to measure reading speed and allow determination of further reading parameters such as reading acuity, reading speed based on reading acuity, critical print size, reading score, and logMAR/logRAD ratio. Such calibrated reading charts have already provided valuable insights into the reading performance of patients in many research studies. They are available in many languages and thus facilitate international communication about near visual performance. In the present review article, the backgrounds of these modern reading charts are presented, and their different levels of test-item standardization are discussed. Clinical research studies are mentioned, and a discussion about the immoderately high number of reading acuity notations is included. Using the logReading Acuity Determination ([logRAD] = reading acuity equivalent of logMAR) measure for research purposes would give reading acuity its own identity as a standardized reading parameter in ophthalmology.

Keywords: Reading acuity; Reading charts; Reading performance; Reading speed; Sentence optotypes.

Fig. 1

Jaeger Schrift-Scalen 1856: (a) German J1 compared with (b) the English J1. (a) Photographic representation of J1 of the German paragraph and (b) J1 of the English paragraph taken from the original Jaeger Schrift-Scalen from 1856 (magnification: 65×). Note that the German version was printed with Gothic letters, while an Antiqua typeface was used for the English version, indicating that even the original version did not represent a comparable international standard

Fig. 2

Bailey–Lovie Word Reading Chart : example of one of the Bailey–Lovie Word Reading Charts (original size: 26.0 cm × 20.5 cm}. Printed with the permission of Ian Bailey

Fig. 3

MNREAD Chart (original size: 46.0 cm x 30.0 cm). Printed with the permission of Gordon Legge

Fig. 4

RADNER Reading Charts: Radner Reading Charts, as exemplified by the German version. Four text reading charts, a page with Landolt rings, and a page with numbers are provided in the booklet (original size: big issue, DIN A4 29.7 cm × 21.0 cm; small issue, DIN A5 21 cm × 14.8 xm)

Fig. 5

The Colenbrander English Continuous Text Near Vision Cards (Original size: 23.0 cm x 18.0 cm) Printed with the permission of August Colenbrander

Fig. 6

SKread paragraph: Example of a paragraph of the SKread Charts. Unrelated words are interrupted by single letters. Printed with the permission of Manfred MacKeben

Fig. 7

Oculus Reading Probe: (Original size: 21.0 cm × 14.8 cm) Printed with the permission of the Oculus Corporation

Fig. 8

Reading speed based upon reading acuity: The figure shows the mean reading speed based upon reading acuity and the mean critical print size for three different age groups. Note the difference in the mean reading speed between the two groups of ages 25 to 38 years and 40 to 53 years and the group of older readers aged 55 to 78 years

Fig. 9

logMAR/logRAD ratio: the logMAR/logRAD ratio shows the reading acuity (logRAD) as a percentage of the distance acuity (logMAR). In this figure, it is exemplified by the logMAR/logRAD ratio of a normally sighted person with healthy eyes and that of patients suffering from AMD. The logMAR/logRAD ratio is considerably lower in AMD patients

Fig. 10

Reading score: the figure exemplifies the reading score per print size obtained from patients with monofocal IOLs reading binocularly, either with best corrected reading acuity or without reading glasses (20 patients were investigated). Although some of the patients could read newspaper-sized print without reading glasses under good light conditions, their reading performance was significantly reduced. The gray area indicates the range of print sizes, from newspaper (left edge) to high-gloss journals (right edge)