Worth 4 Dot test is used to assess for which type of fusion?

Worth 4 Dot test is used to assess for which type of fusion?

• A. Second-degree fusion
• B. Primary fusion
• C. Tertiary fusion
• D. Color vision requirement

Answer: (A)

Binocular fusion status and suppression are what Worth 4 Dot is built to reveal. By having you wear red-green glasses and report what dots you see, the test shows whether both eyes are contributing to the percept and, importantly, how complete that fusion is. This test is especially informative for partial or incomplete fusion—the scenario clinicians describe as second-degree fusion. If fusion is only partial, or if one eye is suppressed under certain conditions, the pattern you report will reflect that partial fusion rather than full, robust fusion. A normal, full (primary) fusion would show fusion across the board with both eyes contributing consistently, while we don’t typically categorize fusion with this test as tertiary. The task isn’t about color vision per se; it’s about whether fusion occurs and to what extent. So, Worth 4 Dot is used to assess second-degree fusion—the partial fusion state between normal fusion and suppression.

Binocular fusion status and suppression are what Worth 4 Dot is built to reveal. By having you wear red-green glasses and report what dots you see, the test shows whether both eyes are contributing to the percept and, importantly, how complete that fusion is.

This test is especially informative for partial or incomplete fusion—the scenario clinicians describe as second-degree fusion. If fusion is only partial, or if one eye is suppressed under certain conditions, the pattern you report will reflect that partial fusion rather than full, robust fusion. A normal, full (primary) fusion would show fusion across the board with both eyes contributing consistently, while we don’t typically categorize fusion with this test as tertiary. The task isn’t about color vision per se; it’s about whether fusion occurs and to what extent.

So, Worth 4 Dot is used to assess second-degree fusion—the partial fusion state between normal fusion and suppression.