Fig. 1

Mean ratings of the evaluation of preventive approaches clustered by user groups. Note User groups were clustered in no current use (“no lifetime use “ or “use  > 12 months ago “), occasional use (“ < 1 × per month” and “1–3 × per month”), and heavy use (“1–2 × per week”, “3–5 × per week”, and “(almost) daily”). The rating scale for preventive measures ranged from −2 to 2 (−2 = “negative”; −1 = “rather negative”; 0 = “neutral”; 1 = “rather positive”; 2 = “positive”). Next to the items, the results of Kruskal–Wallis tests are displayed in parentheses, while significant post-hoc pairwise comparisons with Bonferroni-Holm-correction are shown next to the respective bars