Evaluation of VisionQuest 20/20, a Visual Acuity Testing Software
Condition: Visual Acuity
Study type: Observational

Summary: 
      This study involves the use of VisionQuest 20/20 which is a new software program to test
      visual acuity in children. The purpose of this study is to compare the results of VisionQuest
      20/20 to two other ways to measure visual acuity. The two other tests are a standard eye exam
      by an ophthalmologist and electronic visual acuity (EVA) testing, a computerized version of a
      standard eye test.

      It is important to identify vision problems in children as early as possible. These problems
      include amblyopia ("lazy eye," or reduced vision due to lack of development in the visual
      area of the brain), strabismus (eyes are not aligned correctly due to eye muscle problems),
      and refractive errors (when you need glasses to see up close or far away). Early
      identification of the vision problems allows them to be treated earlier which makes it more
      likely that vision can be improved. VisionQuest 20/20 can be easily distributed to schools,
      and it is easy for the child and the vision screener to use. The test can be performed by
      volunteers instead of an ophthalmologist.
    

Detailed description: 
      Assessing visual acuity represents one of the most sensitive techniques for the detection of
      eye abnormalities in children. Vision disorders are the fourth most common disability in the
      USA and are the most prevalent handicapping condition in childhood. Ocular conditions, if
      undetected or untreated, can have substantial long-term implications for the quality of life
      of the child and the family and can place a burden on public health resources.

      Important causes of visual impairment in children include amblyopia, strabismus and
      significant refractive error. Children with these conditions may benefit from early detection
      to allow treatment. Early detection and treatment is the key for successful management of
      children with visual disorders. If detected during childhood, treatment for amblyopia is
      effective and inexpensive. Although amblyopia is a treatable disorder if detected in
      childhood during the brain's "critical period" for vision development, every year the problem
      goes undetected and untreated in thousands of US children resulting in permanent visual
      disability for the individuals and hundreds of millions of dollars of annual economic loss to
      society. Furthermore, other less serious types of childhood vision problems, such as
      refractive errors, may contribute to academic underperformance if not identified during
      childhood. What ages, venues, and methodologies are best to perform vision screenings and
      when full eye examinations are indicated remains to be determined. , Nevertheless, nearly
      universal agreement exists among U.S. government agencies, health experts, educators, and
      charitable vision organizations that children should be screened for visual disorders, even
      if asymptomatic. To date, a combination of scientific, logistical, economic, and legislative
      shortcomings have prevented vision screening goals from being met for many U.S. children.

      The ideal vision screening method should be accurate (sensitive and specific for clinically
      significant visual problems amenable to treatment), standardized, easy to administer and
      interpret with little training, cost effective, universally available to children, and
      capable of collecting data to ensure medical follow-up is received by those who need it as
      well as to collect epidemiological information and monitor the success of the program year
      after year. The Amblyopia Foundation of America (AFA) has conceptualized how automated
      computer software which assesses vision while a child "plays" a video game could potentially
      meet the requirements for an ideal vision screening system for children old enough to
      cooperate.

      Young children are increasingly familiar with computers and videogames, oftentimes being more
      sophisticated in their use than their parents. Vision screening software is easy to
      distribute via CDs or the internet. Computers are readily available in virtually all schools
      and the cost of computer technology continues to decline even as performance improves.
      Computer software applications allow standardization of logic protocols for vision screenings
      and the videogame format allow for automated testing. Automated testing eliminates the need
      for large scale training and certification of vision screening proctors and instead can allow
      vision screenings to be performed by untrained lay volunteers or personnel already available
      in schools. Finally, since responses of children being tested are inputted directly into the
      computer, results may be printed instantaneously at the end of testing. Computer data may be
      warehoused locally or offsite via the internet to help coordinate medical follow-up for those
      children identified at risk, monitor the success of the program, and facilitate
      epidemiological analysis of vision disorders. Prototype VisionQuest 20/20 software currently
      performs standardized visual acuity assessments of each eye and stereopsis testing while a
      child "plays" a 2-3 minute video game.

      A pilot study (O'Neil J.W., et al 2005 unpublished) suggested lay screeners using this an
      early version of this prototype vision screening software on laptop computers achieved
      similar positive and negative predictive value results to a certified ophthalmic technician
      using a professional grade M&S vision tester. Positive predictive values for clinically
      significant visual disorders were 54% for M&S and 52% for VisionQuest 20/20 respectively.
      Negative predictive values were identical at 97% for each screening method. VisionQuest 20/20
      appears to have potential for use as a vision screener for schoolchildren and may allow more
      children to be reached than manual vision screening or other methods by relying on lay
      personnel already available in schools rather than certified vision screeners or eye
      professionals to perform screenings. Additional benefits include use of computers already
      available in schools with the potential to simplify vision screening logistics and reduce
      costs. Independent validity testing is essential before initiating large scale community
      vision screenings with this new vision screening software. The primary aim of the current
      study is to validate VisionQuest 20/20 screening software by assessing its ability to screen
      for threshold visual acuities as compared to an exact visual acuity obtained with the EVA
      tester using ETDRS optotypes. The secondary aim of the current study is to evaluate the
      ability of VisionQuest 20/20 software to detect the presence or absence of clinically
      significant vision disorders in children as compared to a professional eye examination by a
      pediatric ophthalmologist.
    

Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Healthy children ages 8-5 years with myopia.
      
Keywords: Vision; Visual Acuity