Related Experiment Video
Updated: Dec 21, 2025

Evaluation of a Point-of-Care Testing Analyzer for Measuring Peripheral Blood Leukocytes
Published on: March 22, 2022
Construction and Validation of LEA Hindi Chart: A Multicenter Study
Sourav Datta, Srinivasa Varadharajan1, Deepmala Mazumdar2
1International School of Engineering, Hyderabad, India.
Significance:
This study explains the construction and validation of a chart in Hindi language, one of the commonly spoken languages in the world. The new visual acuity chart is called LEA Hindi chart. The calligraphy construction method described here can help develop other such acuity charts.
Purpose:
The purpose of this study was to construct and validate a new logMAR Hindi visual acuity chart (LEA Hindi chart) using principles similar to that of LEA symbols acuity chart.
Methods:
A multicenter (three centers) study was conducted in two phases. The first phase consisted of identifying and constructing the Hindi optotypes using calligraphy techniques. The Hindi optotypes were calibrated against the Landolt C optotypes by measuring the threshold distance for visual acuity. In the second phase, the newly constructed LEA Hindi chart was validated against the Early Treatment Diabetic Retinopathy Study (ETDRS) and Landolt C visual acuity charts. Sixty participants were enrolled for the first phase (centers 1 and 2) and for the second phase of the study (centers 1 and 3). Additional 15 participants were enrolled (center 1) for testing repeatability.
Results:
Four Hindi optotypes were identified and used for the construction of the chart (first phase). In the second phase, the LEA Hindi chart was found to be comparable with both the Landolt C, (logMAR acuity difference, 0.03 ± 0.13; P > .18) and ETDRS (logMAR acuity difference, -0.02 ± 0.09; P > .25) charts. All the three charts were also found to be repeatable (95% limits of agreement within 0.24 logMAR).
Conclusions:
The newly constructed LEA Hindi visual acuity chart gave comparable levels of visual acuity as that measured in an ETDRS or Landolt C charts. The repeatability was also similar to the standard charts. The LEA Hindi visual acuity chart can be used for patients comfortable with Hindi language and also in studies requiring multiple measurements of visual acuity, to avoid familiarity to a given chart.
More Related Videos
Related Concept Videos
Study Design in Statistics
Does aspirin reduce the risk of heart attacks? Is one brand of fertilizer more effective at growing roses than another? Is fatigue as dangerous to a driver as the influence of alcohol? Questions like these are answered using randomized experiments with proper...
Guidelines and Strategies for Safe Computer Charting
Maintain Confidentiality and Security:
Bioequivalence Data: Statistical Interpretation
Interpreting Run Charts
Statistical Software for Data Analysis and Clinical Trials
Reliability and Validity

