Self-skin Examination for Skin Cancer Detection in High-risk Populations: A Diagnostic Accuracy Study and Implications for Cancer Education.

Background/Purpose: Aquatic populations experience high cumulative ultraviolet radiation exposure and elevated skin cancer risk. Self-skin examination is widely promoted within cancer education strategies; however, its diagnostic accuracy in high-risk groups remains unclear. Method: Adults (≥ 18 years) participating in surfing or outdoor swimming (≥ 1 h/week) underwent full-body skin examination by an accredited skin cancer doctor. Prior to examination, participants identified any lesion(s) of concern, reflecting real-world self-detection. Suspicious lesions were biopsied or excised, with histopathology as the reference standard. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated. Results: Among 191 participants (123 surfers, 68 swimmers), 50.8