The Sun Exposure and Behaviour Inventory (SEBI): validation of an instrument to assess sun exposure and sun protective practices.

BACKGROUND

Skin cancer is the most common cancer worldwide. Sun exposure is the most important risk factor for its development. The amount of exposure required to cause skin cancer has not been quantified, and the impact of sun protective practices is unknown.

OBJECTIVES

To develop a brief self-administered questionnaire to estimate past and current sun exposure, sun protective practices, and assess the questionnaire's reliability and validity.

METHODS

The study had three stages: (1) questionnaire formulation, (2) internal reliability and construct validity testing and questionnaire refinement, (3) test-retest and further internal reliability testing. The final Sun Exposure and Behaviour Inventory (SEBI) is composed of 15 questions assessing three domains; current sun behaviour, current sun exposure and prior sun exposure.

RESULTS

A total of 251 subjects completed Stage 2 testing and 57 completed Stage 3. Final Cronbach's α-scores ranged from 0.71 to 0.84 and k-scores demonstrated excellent to fair/good agreement, indicating acceptable internal consistency and test-retest reliability. Construct validity was evidenced by significantly higher prior sun exposure scores and lower current sun behaviour scores in subjects with a history of non-melanoma skin cancer.

LIMITATIONS: Self-reported questionnaires, though efficient and low cost, may be subject to recall error and bias. Further work remains to determine if the SEBI maintains its reliability and validity in different populations.

CONCLUSION

The SEBI is a brief self-administered questionnaire, which appears to be reliable and valid. It may provide useful measures of past and present sun exposure and current sun behaviour, which may be useful in studies of skin cancer incidence and risk modification.