COMPARATIVE STUDY OF MEASURES OF HETEROPHORIA
Abstract
Three visual screening devices were used to measure heterophoria on 121 subjects who were also tested by the Maddox rod method. A comparison of the data from the two experiments suggests that for the measurement at the near point, the angular deviation of the eyes from the horizontal position is apparently critical. The results obtained when the eyes are in the position usually employed in reading are more consistent than when the near measurement is made with the gaze directed horizontally forward. The data from the two experiments suggest that clinical measurements of heterophoria are more consistent when the examiner adjusts the phorometer prisms than when the subject makes the adjustment. There does not seem to be any justification for the use of arbitrary designations for heterophoria scores in non-clinical terms. Such use of coded digits complicates any statistical analysis of data obtained from visual screening devices. A comparison of the measurements obtained by the Maddox rod method with those obtained by the use of visual screening devices indicates: (a) That visual screening devices are apparently as reliable as the clinical method for the measurement of heterophoria. (b) That the instrument tests do not correlate well with the clinical test; it is possible that this is due to some defect in construction of the devices or in the method of measurement.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 22, 1946
- Accession Number
- AD0663547
Entities
People
- Ellsworth B. Cook
- John H. Sulzman
- Neil R. Bartlett