title: The reliability of the Pelli-Robson contrast sensitivity chart.
abstract: Normative contrast sensitivity (CS) data were obtained using the commercially available Pelli-Robson chart from the dominant eye of 30 young (mean (+/- SD) age 22.5 +/- 4.3 years) and 42 older (mean (+/- SD) age 70.2+/- 6.7 years) subjects with normal healthy eyes. The majority of young subjects were found to have a CS of 1.80 log units or above. The majority of the older subjects were found to have a CS of 1.65 log units or above. CS results were obtained using both sides (A and B) of the Pelli-Robson chart from 30 (15 young and 15 older) of these subjects. These measurements were repeated under identical conditions, 2 weeks later. There was no significant difference between the results from sides A and B of the chart. The CS scores were shown to be repeatable to within +/- 0.15 log units or +/- 1 step. Therefore a significant change in CS score is +/- 2 steps or 0.30 log units. Slight improvements in reliability could be obtained by more careful permutation of letters on each step and a smaller step size. The restriction against these changes is the ensuing increased chart size.
authors.affiliation: Clinical Vision Research Unit, University of Bradford, West Yorkshire, UK.
authors.forename: D B
authors.initials: DB
authors.lastname: Elliott
authors.forename: K
authors.initials: K
authors.lastname: Sanderson
authors.forename: A
authors.initials: A
authors.lastname: Conkey
mesh_terms: D000328:Adult; D000368:Aged; D015350:Contrast Sensitivity; D006801:Humans; D015203:Reproducibility of Results; D014787:Vision Tests / Q000295:instrumentation*