Purpose: To screen for clearness of vision when looking in the distance; to detect myopia (nearsightedness), amblyopia (weakness of sight, lazy eye) and astigmatism (blurred vision).

Equipment

• Distance chart for 10 or 20 feet (should include a 20/25 line), appropriate flash cards or chart for young children
• Occluder (e.g., Lollypop” or “Mardi Gras mask”, occluder glasses, adhesive patches)
• Antibacterial wipes.

Note: Ten-foot chart is preferred for young children.

Recommended acuity screening tools: Visual acuity charts should be according to the child’s developmental level. Any of the following types of visual acuity charts may be used:

• Letter charts (for example HOTV, Sloan Letters, Sloan Numbers)
• Symbol charts (for example, HOTV Symbols, LEA SYMBOL)

Location and Setup

1. Make sure the room in which you are screening is quiet and has no distractions (e.g. pictures, toys).
2. Utilizing a room that is at least 5 foot longer than the distance required for each visual acuity screening and allowing a minimum of 8-10 feet between stations provides less distraction for students and screeners.
3. Make sure that the room is well lit and free from glare. Do not shine a spotlight on the charts. Self-illuminated charts are preferred over non-illuminated charts as yellowing shadows are minimized and the letters are well contrasted. However, clean, white wall charts with clear contrast between the letters and background are acceptable.
4. Mount the chart at the child’s eye level. Adjust the chart height for the size of the person being screened. A suggestion is to place Velcro on the wall and move the chart as needed.
5. Mark off 10 or 20 feet, whichever is appropriate for your chart. The line may be marked with masking tape or paper feet placed on the floor so that the child will be required distance from the chart.
6. The child can be seated or standing but the child’s eyes must be in the direct line above the tape or paper feet.
7. Ask the child to position their heels on the line or other floor marking. Do not allow the child to lean the torso or head forward. If sitting, be sure that the back legs of the chair are on the line.

Procedure

Before screening for visual acuity, orient the child to the screening. Let the child use both eyes to look at the 20/100 letters or symbols to make sure the child can identify the letters or symbols. It may save time to demonstrate to several children how to perform the screening, but the screener should review it with each child to be sure the child is able to perform the task. Demonstrate how to use the occluder.

Screening Session

1. Ask if the child wears glasses. If so, screening should be conducted with glasses. Note on the screening form that the child is wearing glasses.
2. Watch carefully to be sure that the child is not peeking, tilting the head or squinting. If at all possible for young children, have someone stay next to the child and watch closely. Children want to do well on the screening and will often peek, tilt the head, or squint to compensate for vision problems.
3. Do not allow the child to lean the head or torso forward.
4. Begin by screening the right eye, with the left eye occluded.
5. Instruct the child to keep both eyes open and read the selected letter or line of letters with the uncovered eye. Do not use a marking device (pencil/pen) as a pointer to avoid leaving distracting marks on the chart.
6. Start with the 20/50 line and move down to the 20/20 line. If the student is unable to read the 20/50 line, move upward.
7. To receive credit for a line, the child must identify one more than half of the letters/symbols on that line.
8. Do not comment either positively or negatively on the child's responses.
9. If the child is unsuccessful, he or she must be rescreened within 14-21 days prior to referral.
10. It is important to inform the classroom teacher if a child fails the screening so that classroom accommodations can be implemented.
11. Record results - A failed screening followed by a failed rescreening should be referred for further evaluation.

Referral Criteria

Beginning in first grade, each eye must see at least the 20/30 line. If not, the student is to be referred.The important exception is a two-line difference between the two eyes. For example: Right 20/20 Left 20/30 should be referred because there is a two-line difference (the second line being the 20/25 line). For younger children, preschool through kindergarten, each eye must see at least the 20/40 line. The important exception is a two-line difference between the two eyes.

Table 1. Referral Criteria: Preschool and Kindergarten

Table 2. Referral Criteria Grades 1-12