Prevent Blindness America vision screening protocol allow for the use of a 5' testing distance for preschool age children using either HOTV or Lea symbols with linear or single surround with crowding bars formats.
The Preschool Vision Advisory Committee recognizes limited validation of this testing distance to date and therefore encourages additional evidence be collected to further validate this testing distance.
The protocol continues to be supportive of visual acuity testing at 10' using the HOTV or Lea symbols charts.
Justification: Though validation is limited, the VIP study supports the use of a 5' testing distance for preschool age children using either HOTV or Lea symbols with linear or single surround with crowding bars formats. It is further noted that VIP did not clearly delineate the difference between a 5' and a 10' testing distance.
Prevent Blindness America vision screening protocol do not require that added illumination be included on vision screening instruments.
Justification: The Pediatric Vision Screening Advisory Committee defers to existing Prevent Blindness America training protocol which trains screeners to understand proper lighting needs and to ensure proper lighting be included in the selected screening location.
The PlusOptix Vision Screener by PediaVision is approved for use in the Prevent Blindness America vision screening protocol (to be used in the same manner as the SureSight and RetinoMax) for use in screening 3-5 year old children, when used as recommended by the manufacturer.
Justification: While the Pediatric Vision Advisory Committee does not feel the PlusOptix Vision Screener by Pedia Vision can currently serve as a diagnostic tool, its use as a vision screening device within the Prevent Blindness America vision screening protocol is supported by recent studies published in Journal of the American Academy of Pediatric Ophthalmology and Strabismus and Binocular Vision and Strabismus Quarterly.
The approved passing lines for distance visual acuity screening in the Prevent Blindness America vision screening protocol are as follows:
Justification: The recent BPEDS, MEPEDS, and VIP study results support the change from 20/40 to 20/50 for children 3 years of age in the Prevent Blindness America Vision Screening Protocol. (The standards for other ages remain unchanged).
Tracking and convergence testing is not included as a part of the Prevent Blindness America vision screening protocol.
Justification: Tracking and convergence testing is beyond the scope of a screening protocol, as diagnostic skills are required. Evidence is lacking regarding objective ways to measure tracking and convergence testing; interpretation is subjective; and it is difficult to train lay persons.
General Committee Statements:
While the Preschool Vision Advisory Committee recognizes that there are limited studies currently available, it believes that Prevent Blindness America should not rely completely on any one study to determine vision screening protocol, and it should encourage additional studies to be completed.
The appropriate role of the Prevent Blindness America Pediatric Vision Screening Advisory Committee is not to approve particular delivery systems/devices, but rather to approve the standards/protocols that these systems must use - e.g., HOTV/Lea v. Tumbling E; 10' ft distance v. 5' distance - based upon existing evidence. Delivery systems/devices utilized in Prevent Blindness America vision screenings should be compliant with the approved standards/protocols.