title: Development and testing of an automated computer tablet-based method for self-testing of high and low contrast near visual acuity in ophthalmic patients.
abstract: OBJECTIVE
  Many eye diseases require on-going assessment for optimal management, creating an ever-increasing burden on patients and hospitals that could potentially be reduced through home vision monitoring. However, there is limited evidence for the utility of current applications and devices for this. To address this, we present a new automated, computer tablet-based method for self-testing near visual acuity (VA) for both high and low contrast targets. We report on its reliability and agreement with gold standard measures.
  
  
  METHODS
  The Mobile Assessment of Vision by intERactIve Computer (MAVERIC) system consists of a calibrated computer tablet housed in a bespoke viewing chamber. Purpose-built software automatically elicits touch-screen responses from subjects to measure their near VA for either low or high contrast acuity. Near high contrast acuity was measured using both the MAVERIC system and a near Landolt C chart in one eye for 81 patients and low contrast acuity using the MAVERIC system and a 25 % contrast near EDTRS chart in one eye of a separate 95 patients. The MAVERIC near acuity was also retested after 20 min to evaluate repeatability.
  
  
  RESULTS
  Repeatability of both high and low contrast MAVERIC acuity measures, and their agreement with the chart tests, was assessed using the Bland-Altman comparison method. One hundred and seventy-three patients (96 %) completed the self- testing MAVERIC system without formal assistance. The resulting MAVERIC vision demonstrated good repeatability and good agreement with the gold-standard near chart measures.
  
  
  CONCLUSIONS
  This study demonstrates the potential utility of the MAVERIC system for patients with ophthalmic disease to self-test their high and low contrast VA. The technique has a high degree of reliability and agreement with gold standard chart based measurements.
authors.affiliation: Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK.|Vision Science Centre, Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester Royal Eye Hospital, Central Manchester University, Manchester, UK.|Heriot-Watt University, Edinburgh, UK.
authors.forename: Tariq M
authors.initials: TM
authors.lastname: Aslam
authors.affiliation: Vision Science Centre, Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester Royal Eye Hospital, Central Manchester University, Manchester, UK.|Centre for Hearing and Vision Research, Institute of Human Development, University of Manchester, Manchester, UK.
authors.forename: Neil R A
authors.initials: NR
authors.lastname: Parry
authors.affiliation: Vision Science Centre, Hospitals NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester Royal Eye Hospital, Central Manchester University, Manchester, UK.|Faculty of Life Sciences, University of Manchester, Room 3.005, Carys Bannister Building, Dover Street, Manchester, M13 9PL, UK.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Murray
authors.affiliation: Centre for Hearing and Vision Research, Institute of Human Development, University of Manchester, Manchester, UK.
authors.forename: Mahani
authors.initials: M
authors.lastname: Salleh
authors.affiliation: Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK.
authors.forename: Caterina Dal
authors.initials: CD
authors.lastname: Col
authors.affiliation: Faculty of Medical and Human Sciences, University of Manchester, Manchester, UK.
authors.forename: Naznin
authors.initials: N
authors.lastname: Mirza
authors.affiliation: Department of Biostatistics, Faculty of Health and Life Sciences, Department of Eye and Vision Science, University of Liverpool, Liverpool, UK.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Czanner
authors.affiliation: Faculty of Life Sciences, University of Manchester, Room 3.005, Carys Bannister Building, Dover Street, Manchester, M13 9PL, UK. humza.tahir@manchester.ac.uk.
authors.forename: Humza J
authors.initials: HJ
authors.lastname: Tahir
mesh_terms: D000465:Algorithms; D034201:Computers, Handheld; D015350:Contrast Sensitivity / Q000502:physiology*; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D012648:Self Care / Q000379:methods*; D012984:Software; D014786:Vision Disorders / Q000175:diagnosis*; D014787:Vision Tests / Q000295:instrumentation*; D014792:Visual Acuity / Q000502:physiology*
keywords: Low contrast acuity; Psychophysics; Self-testing; Tablet computer; Visual acuity