title: The difference between belief and reality for Viktorin's method of inter-pupillary distance measurement.
abstract: The variation in the measurement of an inter-pupillary distance and monocular centration distance by 54 registered practitioners using a 'pd rule' was investigated. Their estimate of the repeatability of the measurement was also recorded, as was any correction for their own inter-pupillary distance. There was found to be considerable variation between practitioners in all measurements, and the practitioners' estimated repeatability of the measurement was rather better than the reality.
authors.affiliation: Division of Vision Sciences, Glasgow Caledonian University, Cowcaddens Road, Glasgow G4 OBA, UK. gwa@gcal.ac.uk
authors.forename: G
authors.initials: G
authors.lastname: Walsh
authors.forename: E I
authors.initials: EI
authors.lastname: Pearce
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D007498:Iris / Q000033:anatomy & histology*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009907:Optometry / Q000379:methods*; D011680:Pupil / Q000502:physiology*; D012016:Reference Values; D015203:Reproducibility of Results; D013223:Statistics as Topic; D055815:Young Adult