Comparing alternative methods for measuring skin damage

B117

Skin cancer is the most common form of cancer. Ultraviolet (UV) radiation contributes significantly to an individual’s risk for skin cancer. Despite widespread awareness about skin cancer risks, many individuals continue to expose themselves to large amounts of UV radiation and protect their skin minimally. Self-report is the most commonly used strategy for measuring skin color, skin sensitivity, skin risk and protective behaviors, and perceived cumulative damage to the skin. Therefore, it is important to determine how accurate self-perception or self-report is, particularly when it is used as an outcome for intervention studies. In addition to self-report, however, there are other measurement options such as observation and visual inspection, UV-filtered photography showing underlying skin damage, and skin reflectance measuring current skin color. Research is limited to date as to how these measures compare to one another in terms of reliability and validity. The current study sought to investigate the reliability and validity of four measurement strategies and explore the differential validity of these measures based on demographic the characteristics of the sample. Participants were 100 young adults from the Philadelphia area who were recruited from three college campuses to take part in a larger study testing several behavioral skin cancer prevention interventions. Participants completed an online survey and attended an in-person session in which an observer rated their skin color; additionally, UV photos and spectrophotometry readings were taken. Trained research assistants rated the damage depicted in the UV photos reliably (k = .86). Moderate to high correlations emerged between self-report and the gold-standard, skin reflectance spectrophotometery. Observer rating correlated with spectrophotometry rating of current but not natural skin color. Overall, lighter-skinned individuals (by any measure) reported more cumulative skin damage, which was confirmed by UV photography. Although women’s current skin color was lighter and their UV photos showed less damage than men’s, women reported their skin to be more damaged than men did. These findings suggest that self-report continues to be a valuable measurement strategy when skin reflectance is not feasible or appropriate and that UV photos may also be useful but need to be tested further. Observer rating of skin color may be improved with more comprehensive protocols or training. The results also suggest that more intensive skin cancer prevention interventions may be important for men. Future research should continue to test these measurement strategies with larger and more diverse populations and compare them with other types of measures such as behavioral observation or objective measurement of UV exposure or protective behaviors.