title: Self-reported skin colour and erythemal sensitivity vs. objectively measured constitutive skin colour in an African population with predominantly dark skin.
abstract: BACKGROUND
  Skin colour is an important factor in skin-related diseases. Accurate determination of skin colour is important for disease prevention and supporting healthy sun behaviour, yet such data are lacking for dark skin types.
  
  
  METHODS
  Self-perceived, natural skin colour and sun-skin reaction were compared with objectively measured skin colour among an African population with predominantly dark skin. Unexposed skin of 556 adults (70.1% Black) was measured with a reflectance spectrophotometer to calculate an individual typology angle (°ITA). Participants reported self-perceived skin colour and erythemal sensitivity.
  
  
  RESULTS
  There was a strong, positive monotonic correlation between self-reported and measured skin colour (Spearman ρ = 0.6438, P < 0.001), but only a weak correlation between self-reported erythemal sensitivity and measured skin colour (Spearman ρ = 0.2713, P < 0.001). Self-report biases in underestimation and overestimation of skin colour were evident. Many participants with 'dark brown' and 'black' skin had difficulty in classifying erythemal sensitivity.
  
  
  CONCLUSIONS
  In Africa, self-reported skin colour could potentially be used in lieu of spectrophotometer measurements, but options for questions on sunburn and tanning require suitable adjustment. Our study provides evidence of range in °ITA values among residents in Africa and reinforces previous results that self-report may be reliable for determining skin colour, but not erythemal sensitivity, for dark skin individuals.
authors.affiliation: Environment & Health Research Unit, South African Medical Research Council, Pretoria, South Africa.|Department of Geography, Meteorology and Geoinformatics, University of Pretoria, Pretoria, South Africa.|Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
authors.forename: Caradee Y
authors.initials: CY
authors.lastname: Wright
authors.affiliation: Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY, USA.
authors.forename: Marcus
authors.initials: M
authors.lastname: Wilkes
authors.affiliation: Occupational Hygiene and Health Research Initiative, North-West University, Potchefstroom, South Africa.
authors.forename: Johan L
authors.initials: JL
authors.lastname: du Plessis
authors.affiliation: Cancer Society of New Zealand Social and Behavioural Research Unit, Department of Preventive and Social Medicine, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand.
authors.forename: Anthony I
authors.initials: AI
authors.lastname: Reeder
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044383:Black People; D004890:Erythema / Q000175:diagnosis* / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D057566:Self Report; D012867:Skin / Q000528:radiation effects*; D012880:Skin Pigmentation; D013053:Spectrophotometry; D013472:Sunlight / Q000009:adverse effects; D055815:Young Adult
keywords: Africa; erythemal sensitivity; self-report; skin colour; spectrophotometer