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Updated: Aug 8, 2026

Pharmacologic Induction of Epidermal Melanin and Protection Against Sunburn in a Humanized Mouse Model
Published on: September 7, 2013
Using structural equation modeling to examine factors that influence sunburn frequency and severity among adults
J A Shoveller1, P A Ratner, J L Johnson
1Department of Health Care and Epidemiology and Centre for Community Health and Health Evaluation Research, University of British Columbia, Vancouver, Canada.
Abstract:
This study uses structural equation modeling to examine hypothesized relationships between sunburn and physical characteristics and potentially modifiable behavior. The analysis was based on self-reported data collected from a randomly selected national sample of Canadian adults. An initial model was tested with 50% of the cases (n = 1,408); the remaining cases (n = 1,298) were reserved for confirmatory testing. After the initial model failed, theoretically plausible effects were added incrementally to improve overall model fit. The initial model yielded: chi2(68 d.f.) = 3199.41 (P < .001) and the AGFI = .56. With 32 added effects, a fit model resulted in: chi2(36 d.f.) = 394.35 (P < .001), AGFI = 0.87, and IFI = 0.91 (the Critical-N was 210). Model fit was confirmed. Suntanning, failure to wear protective clothing, and sun exposure were associated with the frequency of severity-adjusted sunburns. Sunscreen use was not associated with sunburn frequency-severity.
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