title: Longitudinal study of visual discomfort symptoms in college students.
abstract: OBJECTIVE
  To determine the variation of visual discomfort symptom reporting in a group of college students over a 1 year period.
  
  
  METHODS
  Subjects were screened for visual acuity and uncorrected refractive error before participating in the study. A survey of visual discomfort developed by Conlon et al., Vis Cogn 1999;6:637-666, and the Convergence Insufficiency Symptom Survey (CISS) were administered to a group of 23 college students twice with approximately 1 year between administrations. All subjects also completed two clinical assessments of accommodation and vergence.
  
  
  RESULTS
  The mean time between administrations of the symptom surveys was 13 months. There was no clinically significant mean difference between the first and second administration of both visual discomfort surveys. The intraclass correlation coefficient was 0.82 for the Conlon et al., Vis Cogn 1999;6:637-666 survey and 0.85 for the CISS. The 95% limits of agreement for the Conlon et al., Vis Cogn 1999;6:637-666 survey was -18.44, 17.92 and for the CISS was -14.36, 13.36. The intraclass correlation coefficient values for the optometric tests ranged from 0.38 to 0.83.
  
  
  CONCLUSIONS
  Visual discomfort symptoms were found to be stable in the majority of young college students over a 1 year period. However, a minority of students showed large variability between the two administrations of the surveys.
authors.affiliation: Southern California College of Optometry, 2575 Yorba Linda Boulevard, Fullerton, CA 92831, USA. eborsting@scco.edu
authors.forename: Eric
authors.initials: E
authors.lastname: Borsting
authors.forename: Chris
authors.initials: C
authors.lastname: Chase
authors.forename: Chinatsu
authors.initials: C
authors.lastname: Tosha
authors.forename: William H
authors.initials: WH
authors.lastname: Ridder
mesh_terms: D000065:Accommodation, Ocular; D001248:Asthenopia / Q000503:physiopathology*; D003290:Convergence, Ocular; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D015835:Ocular Motility Disorders / Q000503:physiopathology; D012720:Severity of Illness Index; D013334:Students; D055815:Young Adult