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Purpose Amblyopia is a disorder of visual processing. There is evidence that the parvocellular pathway, which prefers chromatic stimuli, is selectively damaged in amblyopia. Consistent with this hypothesis, previous studies have demonstrated that patients with amblyopia show poorer performance on colour vision tests. Methods Ten adult amblyopic subjects (3 strabismic, 5 anisometropic and 3 mixed) were tested using the Farnsworth Munsell 100 Hue (FM100Hue)colour vision test. In separate testing sessions, positive spherical lenses were used to induce blur in the fellow eye (FFE)to match the near acuity of the amblyopic eye (AME). The test (all boxes)was performed under five conditions(randomised): AME,FFE,binocularly (BIN),FFE with blur and BIN with the FFE blurred. Age matched controls were included to assess the effect of defocus in normal subjects, with blur placed in front of the non‐dominant eye to induce mild, moderate or severe blur. Results Amblyopic participants performed well in the FM100Hue test, with scores falling within normal age means in 9/11 subjects (in the AME). Strabismic amblyopes had a more pronounced deficit in error scores. Across all amblyopic subjects, performance was significantly beter under BIN conditions (p=0.023). Induced blur in controls only affected error scores under the severe blur condition, and had litle effect in amblyopic participants. Conclusion This study has shown that amblyopes perform well in this commonly performed colour vision test, and demonstrated improved test performance under binocular conditions. The low spatial frequency of the stimuli may allow for extensive pooling of chromatic information therefore allowing performance of this test to be robust to a parvocellular dysfunction. [ABSTRACT FROM AUTHOR]