Adult 1 Article 1 Health Communication 1 Health communication 1 Humans 1 Male 1 Optimistic bias Radon 1 Risk 1 Risk perception 1 Smoking 1 Synergistic risk 1 adult 1 attitude to health 1 cancer risk 1 controlled study 1 environmental exposure 1 female 1 high risk population 1 human 1 low risk population 1 lung cancer 1 male 1 medical information 1 nonsmoker 1 procedures 1 public health message 1 publication 1 radon 1 randomized controlled trial 1