Measuring sun exposure habits and sun protection behaviour using a comprehensive scoring instrument--an illustration of a possible model based on Likert scale scorings and on estimation of readiness to increase sun protection

Background: Few attempts to present a comprehensive scoring instrument for sun exposure and protection have been made. The present paper aims to describe a possible set of questions suitable for such an instrument, comprising the most important aspects of sun exposure and protection. Methods: The material from a previously performed intervention study, using a questionnaire based on Likert scales and on the Transtheoretical Model of Behaviour Change (TTM), was utilised. 213 primary healthcare patients filled in the questionnaire and were randomised into two groups receiving sun protection advice, in Group 1 in letter-form, and in Group 2 orally during a doctor's consultation. In the original study, increased sun protection/readiness to increase sun protection was demonstrated for several items in Group 2, at six months. To compose a comprehensive scoring instrument, five questions concerning sun exposure/protection (intentional tanning, sunscreen use, choice of SPF, number of occasions with sunburn, and time spent in the sun at midday), were selected to give a 20 point behavioural score. Similarly, four TTM-based questions (giving up sunbathing, using clothes for sun protection, using sunscreens, and staying in the shade) gave a 16 point “propensity-to-change”-score. Results: At follow-up, increased sun protection reflected in the behavioural score occurred only in Group 2 (p < 0.001). For the propensity-to-change-score, increased readiness to increase sun protection occurred in both groups, but the change was significantly higher in Group 2 (p < 0.05). Categorisation of the 20 point behavioural score, into three risk levels, revealed a significantly higher shift of subjects moving to a lower risk level in Group 2 compared to Group 1 (p < 0.05). Conclusions: In conclusion, twinning of a summarised Likert scale behavioural score with a TTM-based propensity-to-change-score seems promising for the creation of a questionnaire-based, comprehensive scoring instrument for sun exposure and protection.