title: The SPARCS: a novel assessment of contrast sensitivity and its reliability in patients with corrected refractive error.
abstract: OBJECTIVE
  To explore the reliability of the Spaeth/Richman Contrast Sensitivity (SPARCS) test and to assess the contrast sensitivity (CS) distribution among subjects with various refractive errors.
  
  
  METHODS
  Cross-sectional study. Ninety-three individuals (182 eyes) with varying amounts of refractive error were included in this study and divided into six groups according to their spherical equivalent. CS was evaluated using Pelli-Robson (PR) and SPARCS assessments. Each eye was tested twice with both measurements. Outcomes included the correlations of PR and SPARCS scores, the test-retest agreement of the two measurements and the limits of agreement between tests of CS measurements. The distribution of CS among the six groups was compared.
  
  
  RESULTS
  Pearson correlation analysis showed statistically significant correlations between SPARCS and PR scores (p<0.001). Reliability analysis showed that SPARCS had better test-retest agreement than PR, with SPARCS exhibiting a higher intraclass coefficient (ICC=0.635). Bland-Altman plots showed that the mean difference of measurements was close to 0 for both CS measurements. Among the six refractive groups, there were no significant differences in CS scores with either measurement.
  
  
  CONCLUSIONS
  SPARCS appears to be a reliable assessment for CS. The difference in CS among myopes, emmetropes and hyperopes wearing their habitual correction was statistically insignificant in this study.
  
  
  BACKGROUND
  NCT01300949, post results.
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: Elif
authors.initials: E
authors.lastname: Erdem
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: Andrew
authors.initials: A
authors.lastname: Lyu
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: Camila
authors.initials: C
authors.lastname: Zangalli
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: Sheryl S
authors.initials: SS
authors.lastname: Wizov
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: David
authors.initials: D
authors.lastname: Lo
authors.affiliation: Department of Glaucoma, Wills Eye Hospital, Philadelphia, Pennsylvania, USA.
authors.forename: Eric E
authors.initials: EE
authors.lastname: Spaeth
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: Jesse
authors.initials: J
authors.lastname: Richman
authors.affiliation: Department of Ophthalmology, Glaucoma Research Center, Wills Eye Hospital, Jefferson Medical College, Philadelphia, Pennsylvania, USA.
authors.forename: George L
authors.initials: GL
authors.lastname: Spaeth
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015350:Contrast Sensitivity / Q000502:physiology*; D003430:Cross-Sectional Studies; D005139:Eyeglasses; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011788:Quality of Life; D012372:ROC Curve; D012030:Refractive Errors / Q000503:physiopathology* / Q000628:therapy; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires; D014787:Vision Tests / Q000379:methods*; D055815:Young Adult
keywords: Diagnostic tests/Investigation; Imaging; Visual perception