Reliability of the compensation comparison method for measuring retinal stray light studied using Monte-Carlo simulations

J Biomed Opt. 2006 Sep-Oct;11(5):054010. doi: 10.1117/1.2357731.

Abstract

Recently the psychophysical compensation comparison method was developed for routine measurement of retinal stray light. The subject's responses to a series of two-alternative-forced-choice trials are analyzed using a maximum-likelihood (ML) approach assuming some fixed shape for the psychometric function (PF). This study evaluates the reliability of the method using Monte-Carlo simulations. Various sampling strategies were investigated, including the two-phase sampling strategy that is used in a commercially available instrument. Results are given for the effective dynamic range and measurement accuracy. The effect of a mismatch of the shape of the PF of an observer and the fixed shape used in the ML analysis was analyzed. Main outcomes are that the two-phase sampling scheme gives good precision (Standard deviation = 0.07 logarithmic units on average) for estimation of the stray light value. Bias is virtually zero. Furthermore, a reliability index was derived from the responses and found to be effective.

Publication types

  • Evaluation Study

MeSH terms

  • Computer Simulation
  • Humans
  • Light
  • Models, Biological*
  • Models, Statistical
  • Monte Carlo Method
  • Psychometrics / methods
  • Refraction, Ocular / physiology*
  • Refractometry / methods*
  • Reproducibility of Results
  • Retina / anatomy & histology*
  • Retina / physiology*
  • Retinoscopy / methods*
  • Scattering, Radiation
  • Sensitivity and Specificity
  • Vision Tests / methods*