Reading is a fundamental activity of daily living that reflects the overall vision capacity. Therefore, it is no surprise that the evaluation of the reading ability is among the routine tests in a standard ophthalmological examination. However, the prevalent reading tools that we use in clinical settings for the assessment of near vision (ie. the Jaeger charts) fail to reflect the whole spectrum of vision capacity for near and intermediate distances and provide mainly quantitative information with average repeatability.

For the reliable evaluation of the near and intermediate vision, advanced reading tools like the MNREAD and the Radner reading charts have been developed, which assess various parameters like reading speed and critical print size.

A Greek printed version of the MNREAD chart (MNREAD-GR) has been developed and validated by the Aristotle University of Thessaloniki. All three sub-versions of the Greek MNREAD that were developed, proved to be valid for comparative studies in research and clinical settings for low and normal vision patients.

Migration to digital reading is a reality for the western citizens in the 21st century. Reading on computers, laptops and other digital screens permit the easy manipulation of the text size, contrast, color and font size, enabling even low or very-low vision patients to read. Moreover, video screen technology allows for the development of contemporary reading tools and applications in a single device that can be upgraded if or when the new version becomes available.

DDART is a digital reading test for near and intermediate vision that was developed and validated at the Department of Ophthalmology of the Democritus University of Thrace. It incorporates the fundamental principles of the printed MNREAD-GR and calculates the following parameters.

Reading speed: the reading speed of the current sentence (in words per minute - wpm). It is calculated by the following formula:

Reading speed = 60 × (10 – errors) / (time in seconds)

where errors is the number of mistakes made by the patient in the current sentence and time (in seconds) is the patient’s reading duration of the current sentence

Reading acuity (RA): the smallest print that can be read by the patient easily (in logMAR). It is calculated by the following formula:

RA = 1.4 - (sentences × 0.1) + (errors × 0.01)

Maximum Reading Speed (MRS): is defined as the patient’s reading speed (in wpm) when reading is not limited by print size. It is calculated by averaging the reading speed of the sentences with print size larger than the critical print size (CPS).

Critical Print Size (CPS): is defined as the smallest print size (in logMAR) that can be read with the maximum reading speed, ie., with speed greater than or equal to the average reading speed of the larger logMAR print sentences minus 1.96 times the standard deviation (SD) of the reading speed of these sentences.

Reading Accessibility Index (ACC): is defined as the mean reading speed of the 10 largest print sizes of the MNREAD Acuity Chart at 40 cm (1.3 to 0.4 logMAR), divided by 200 wpm, which is the mean reading speed of normally sighted young adults aged 18 to 39 years old. This parameter was designed for better evaluation of one’s access to text across the range of the 10 most common print sizes found in everyday life.

Based on the fundamental properties of DDART, which is an executable program for MS Windows, a web-based version of DDART, called wDDART, was developed and validated in the Department of Ophthalmology of the Democritus University. The new wDDART does not require installation to a host computer and displays sentences with text sizes from 1.3 to -0.5 logMAR for different patient-screen distances. It automatically calculates the same reading parameters with DDART (RA, MRS, CPS, ACC) providing advanced text calibration features and monitoring examination distance using computer vision techniques.