PT - JOURNAL ARTICLE AU - Reeder, Anthony I. AU - Hammond, Vanessa A. AU - Gray, Andrew R. TI - Questionnaire Items to Assess Skin Color and Erythemal Sensitivity: Reliability, Validity, and “the Dark Shift” AID - 10.1158/1055-9965.EPI-09-1300 DP - 2010 May 01 TA - Cancer Epidemiology Biomarkers & Prevention PG - 1167--1173 VI - 19 IP - 5 4099 - http://cebp.aacrjournals.org/content/19/5/1167.short 4100 - http://cebp.aacrjournals.org/content/19/5/1167.full SO - Cancer Epidemiol Biomarkers Prev2010 May 01; 19 AB - Background: Skin pigmentation is a key factor for UV radiation exposure related cancers. To appropriately target cancer control activities related to this exposure and for better representation in epidemiologic studies, a valid and reliable assessment of skin color is required.Methods: The validity and reliability of two self-report measures were assessed: skin color and erythemal sensitivity. A sample of 289 university students categorized their unexposed skin color and photosensitivity via a questionnaire. Skin color was also measured by spectrophotometer. After 7 days, participants repeated the self-report assessment.Results: Significant correlations were found for both self-report items with objective measures, indicating that these items may be valid assessment tools (color: Spearman's ρ = −0.75, P < 0.001; photosensitivity: Spearman's ρ = −0.64, P < 0.001). No sex differences in validity were evident. Stronger correlations were found among those of European than those of non-European ethnicity (color: Spearman's ρ = −0.78 versus −0.59, bootstrap P = 0.007; photosensitivity: Spearman's ρ = −0.63 versus −0.28, bootstrap P = 0.001). Strong biases toward overestimation of skin pigmentation were evident, ranging from 36% in the self-identified fair skin group to 77% in the medium skin color group. Intrarater reliability of the questionnaire items was high (color: k = 0.78, P < 0.001; photosensitivity: k = 0.77, P < 0.001).Conclusions: Study findings suggest that self-report may be a valid measurement strategy when assessing skin type, but there is a bias toward overestimation of skin color and, potentially, UV radiation resilience.Impact: This bias has the potential to undermine the effectiveness of skin cancer prevention efforts and needs to be addressed in health promotion programs. Cancer Epidemiol Biomarkers Prev; 19(5); 1167–73. ©2010 AACR.