title: [Reproducibility of subjective refraction measurement].
abstract: BACKGROUND
  Reproducibility of subjective refraction measurement is limited by various factors. The main factors affecting reproducibility include the characteristics of the measurement method and of the subject and the examiner.
  
  
  RESULTS
  This article presents the results of a study on this topic, focusing on the reproducibility of subjective refraction measurement in healthy eyes. The results of previous studies are not all presented in the same way by the respective authors and cannot be fully standardized without consulting the original scientific data. To the extent that they are comparable, the results of our study largely correspond largely with those of previous investigations: During repeated subjective refraction measurement, 95% of the deviation from the mean value was approximately ±0.2 D to ±0.65 D for the spherical equivalent and cylindrical power. The reproducibility of subjective refraction measurement in healthy eyes is limited, even under ideal conditions.
  
  
  CONCLUSIONS
  Correct assessment of refraction results is only feasible after identifying individual variability. Several measurements are required. Refraction cannot be measured without a tolerance range. The English full-text version of this article is available at SpringerLink (under supplemental).
authors.affiliation: Fachhochschule Lübeck, Mönkhofer Weg 239, 23562, Lübeck, Deutschland, grein@fh-luebeck.de.
authors.forename: H-J
authors.initials: HJ
authors.lastname: Grein
authors.forename: O
authors.initials: O
authors.lastname: Schmidt
authors.forename: A
authors.initials: A
authors.lastname: Ritsche
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012029:Refraction, Ocular / Q000502:physiology*; D015203:Reproducibility of Results; D042262:Retinoscopy / Q000379:methods*; D012680:Sensitivity and Specificity