Table 3 Characteristics of the participants assessed for undiagnosed colour vision deficiency (CVD).

From: Colour vision deficiency and sputum colour charts in COPD patients: an exploratory mixed-method study

  Age Sex COPD Smoking pack-year history Associated medical conditions Colour vision deficiency
  69 Male 34 Cataracts No CVD
  20 Female x 0 Stargardt’s macular dystrophy Protanopia
  23 Female x 0 Type 1 diabetes mellitus Tritanopia
  78 Male 30 Type 1 diabetes mellitus No CVD
  75 Female 26 Type 2 diabetes mellitus; cataracts Protanopia
  72 Female 75 Type 2 diabetes mellitus; cataracts No CVD
  20 Female x 0 Type 1 diabetes mellitus No CVD
  74 Female 22 Cataracts Tritanopia
  62 Male 49 N/A No CVD
  73 Male 90 N/A Tritanopia
  75 Male 32 N/A Tritanopia
  83 Male 44 Type 2 diabetes mellitus; cataracts Protanopia and tritanopia
  64 Male 38 N/A No CVD
Median (IQR) 72 (20) 32 (22)