title: Utility and uncorrected refractive error.
abstract: OBJECTIVE
  To investigate utility (a preference-based quality of life [QoL] measure) associated with uncorrected refractive error (URE).
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  A cohort of 341 consecutive patients 40 to 65 years of age with refractive error and no ocular disease impairing vision worse than 20/25 (0.1 logarithm of the minimum angle of resolution [logMAR] units) in the better eye. Without vision correction, 30 had no vision impairment, 65 had only distance vision impairment (DVI), 97 had only near vision impairment (NVI), 112 had moderate amounts of both distance and near vision impairment (DNVI), and 37 had severe impairment (distance or near worse than 20/200 [>1.0 logMAR]) in the better eye.
  
  
  METHODS
  All participants underwent a comprehensive eye examination with refraction, aided and unaided visual acuity (VA) at 6 m and 40 cm, and ocular health assessment. Utilities were elicited for a number of scenarios using a standardized, face-to-face time trade-off (TTO) interview method.
  
  
  METHODS
  The main outcome measure was TTO utility for the participant's own uncorrected vision state. Utilities ranged from 0 to 1, where 0 = death and 1 = perfect vision, and were scaled to account for comorbidities so that 1 = perfect health (adjusted utility).
  
  
  RESULTS
  Unaided VA was 0.50 ± 0.24 logMAR at distance in the DVI group, 0.43 ± 0.17 logMAR at near in the NVI group, and 0.72 ± 0.36 and 0.56 ± 0.29 at distance and near, respectively, in the DNVI group. Adjusted utilities for the 3 groups were 0.82 ± 0.16 in the DVI group, 0.81±0.17 in the NVI group, and 0.68 ± 0.25 in the DNVI group. The DVI and NVI group utilities (adjusted and unadjusted) did not differ significantly (P = 0.73 and P = 0.77, respectively). The DNVI utility was significantly worse than that of the DVI and NVI groups (adjusted and unadjusted, P<0.01).
  
  
  CONCLUSIONS
  The URE is associated with measurable reductions in utility (and therefore QoL). Reductions are similar regardless of whether near or distance vision is impaired, but worse when both are impaired. The results underscore the significance of the effect of URE on QoL, particularly with respect to uncorrected presbyopia, which has been a relatively neglected area in research and policy. The utility figures in this study can be used as inputs for cost-effectiveness studies relating to URE to assist resource allocation decisions.
  
  
  BACKGROUND
  The author(s) have no proprietary or commercial interest in any materials discussed in this article.
authors.affiliation: Brien Holden Vision Institute, Sydney, Australia. n.tahhan@brienholdenvision.org
authors.forename: Nina
authors.initials: N
authors.lastname: Tahhan
authors.forename: Eric
authors.initials: E
authors.lastname: Papas
authors.forename: Timothy R
authors.initials: TR
authors.lastname: Fricke
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Frick
authors.forename: Brien A
authors.initials: BA
authors.lastname: Holden
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005260:Female; D006304:Health Status; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D012029:Refraction, Ocular / Q000502:physiology; D012030:Refractive Errors / Q000523:psychology* / Q000628:therapy; D015203:Reproducibility of Results; D018434:Sickness Impact Profile; D014792:Visual Acuity / Q000502:physiology; D019987:Persons with Visual Disabilities / Q000523:psychology*