色誤認の実態を反映する新しい色覚検査の試み

New color vision tests to evaluate faulty color recognition

　色覚異常者における色誤認の実態を評価するために，従来の色覚検査とは異なった視点から2種類の新しい検査法を考案した。1つは順不同に示した赤，緑灰，黄，青の5色，計10本の線から，赤，緑，灰色の線を選択させ，もう1つは，多数の緑の葉の中に配置した10個の赤いツツジの花を指摘させるものである。これを15〜40歳の色覚正常者20名と色覚異常者75名で検討した結果2色型と異常3色型，異常3色型と色覚正常者間でそれぞれ正答数に有意差が示された。

　本検査は色覚異常者に日常生活のなかで無意識に生じている色誤認を反映すると考えられ，簡便かつ鋭敏で再現性にも優れており，職業適性を判断する指標などに発展させることが可能である。

Two new types of color vision tests were designed to assess faulty color recognition in color vision deficiencies based on principles as are different from conventional color vision tests. In one, the subject is asked to choose either of red, green and gray lines among 10 lines that are randomly colored in red, green, gray, yellow or blue. In the other, the subject is asked to select a total of 10 red azalea blossoms dispersed among numerous green leaves. Seventy-five congenital color-deficient persons and 20 normal subjects were examined. As a result, the number of correct answers differed significantly between dichromats and anomalous trichromats, and between anomalous trichromats and normal subjects. These tests are easy, sensitive and reproducible. They reflect the faulty color recognition that occurs unconsciously in color-deficient persons in their daily lives and may be useful in judging the qualifications required in their occupations.