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Evaluating a Bilingual, Community-Based Skin Cancer Education Program in an Underserved Hispanic Population: An Item
Smaran Marupudi1, Natasha N Quailes2, Jared Hensley1
1Dermatology, The University of Texas Rio Grande Valley School of Medicine, Edinburg, USA.
Background:
Skin cancer prevention is often underemphasized in medically underserved regions such as the Rio Grande Valley (RGV), where residents, predominantly Hispanic and lower-income individuals, face limited access to dermatologic care and may be unaware of their risk for skin cancer.
Methods:
The intervention included a bilingual educational session with a board-certified dermatologist and a seven-item knowledge survey administered before and immediately after the session, adapted from a previously validated instrument. A convenience sample of 73 participants completed both surveys. The instrument, adapted for this population, was evaluated using a two-parameter Item Response Theory (IRT) model to estimate participants' underlying knowledge proficiency (theta) beyond raw scores. Panel regression was used to assess how demographic variables, including age, gender, education, income, rural residence, and language, predicted knowledge change. A post hoc content validity index (CVI) was conducted with 10 experts from dermatology and public health.
Results:
Results revealed small-to-moderate improvements in knowledge scores across the sample, with question 5 (tan damage) and question 6 (sunscreen application) exhibiting the highest information at lower knowledge levels. Bilingual language use and higher education levels were positively associated with higher knowledge scores, while older age and rural residence were linked to smaller improvements. Variation between theta values and raw scores highlighted variability in learning outcomes, supporting the use of IRT to capture nuanced change. Results of the CVI revealed scores of 0.99 for relevance, 0.90 for clarity, 0.96 for representativeness, and 0.96 for cultural appropriateness.
Conclusion:
This intervention demonstrates the feasibility of a bilingual, community-driven education effort and utilized IRT to identify strengths and weaknesses of individual survey items. It provides evidence to guide refinement of future skin cancer educational assessment tools and interventions for underserved Hispanic populations such as the RGV.
