title: Designing a new test for contrast sensitivity function measurement with iPad.
abstract: OBJECTIVE
  To introduce a new application (ClinicCSF) to measure Contrast Sensitivity Function (CSF) with tablet devices, and to compare it against the Functional Acuity Contrast Test (FACT).
  
  
  METHODS
  A total of 42 subjects were arranged in two groups of 21 individuals. Different versions of the ClinicCSF (.v1 and .v2) were used to measure the CSF of each group with the same iPad and the results were compared with those measured with the FACT. The agreements between ClinicCSF and FACT for spatial frequencies of 3, 6, 12 and 18 cycles per degree (cpd) were represented by Bland-Altman plots.
  
  
  RESULTS
  Statistically significant differences in CSF of both groups were found due to the change of the ClinicCSF version (p<0.05) while no differences were manifested with the use of the same FACT test. The best agreement with the FACT was found with the ClinicCSF.v2 with no significant differences in all the evaluated spatial frequencies. However, the 95% confidence intervals for mean differences between ClinicCSF and FACT were lower for the version which incorporated a staircase psychophysical method (ClinicCSF.v1), mainly for spatial frequencies of 6, 12 and 18 cpd.
  
  
  CONCLUSIONS
  The new ClinicCSF application for iPad retina showed no significant differences with FACT test when the same contrast sensitivity steps were used. In addition, it is shown that the accurateness of a vision screening could be improved with the use of an appropriate psychophysical method.
authors.affiliation: Centro de Tecnologías Físicas, Universitat Politècnica de València, 46022 Valencia, Spain; Departamento de Óptica, Universitat de València, 46100 Burjassot, Spain. Electronic address: marodva1@upvnet.upv.es.
authors.forename: Manuel
authors.initials: M
authors.lastname: Rodríguez-Vallejo
authors.affiliation: Centro de Tecnologías Físicas, Universitat Politècnica de València, 46022 Valencia, Spain.
authors.forename: Laura
authors.initials: L
authors.lastname: Remón
authors.affiliation: Centro de Tecnologías Físicas, Universitat Politècnica de València, 46022 Valencia, Spain.
authors.forename: Juan A
authors.initials: JA
authors.lastname: Monsoriu
authors.affiliation: Departamento de Óptica, Universitat de València, 46100 Burjassot, Spain.
authors.forename: Walter D
authors.initials: WD
authors.lastname: Furlan
mesh_terms: D000328:Adult; D034201:Computers, Handheld; D015350:Contrast Sensitivity; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014786:Vision Disorders / Q000175:diagnosis*; D014787:Vision Tests / Q000295:instrumentation*; D055815:Young Adult
keywords: Contrast sensitivity function; Desempeño visual; Dispositivos de tableta; EFAC; FACT; Función de sensibilidad al contraste; Tablet devices; Visual performance; iPad