Suggested FD2 stereoacuity norms (seconds of arc) (SD) for children ⩾48 months and <48 months performing the test at 6 metres.
| Mean age | Mean stereoacuity (seconds of arc) at 6 metres test distance (SD) |
|---|---|
| Age ⩾48 months (n = 29) | 30 (13) |
| Age<48 months (n = 13) | 50 (8) |
| Total number | 42 |