Table 2.

Risk Perception Items, Descriptive Statistics, and Reliability

Scale/item	M ± SD
PV-child total score (Cronbach’s α = .86)	14.71 ± 4.08
How concerned are you that smoking will make your child’s asthma worse? (1 = not at all, 4 = very much)
How much do you believe that your smoking is related to your child’s asthma symptoms? (1 = not at all, 4 = very much)
How much do you believe that your smoking increases the frequency of your child’s asthma attacks? (1 = not at all, 4 = very much)
How much do you believe that your smoking affects how bad your child’s asthma is? (1 = not at all, 4 = very much)
How much do you believe that your smoking increases the chance that your child will have to go to the emergency room or be hospitalized for an asthma attack? (1 = not at all, 4 = very much)
PE-child total score (Cronbach’s α = .94)	14.74 ± 4.49
If you stop smoking, how much do you think that would make your child’s asthma symptoms better? (1 = not at all, 4 = very much)
If you stop smoking, how much do you think that would decrease the how often your child has asthma symptoms? (1 = not at all, 4 = very much)
If you stopped smoking how much do you think that would decrease how bad your child’s asthma symptoms are? (1 = not at all, 4 = very much)
If you stopped smoking, what are the chances that your child’s asthma would get better? (1 = not at all, 4 = very much)
If you stopped smoking how much do you think that would decrease the chance that your child will have to go to the emergency room or be hospitalized for an asthma attack? (1 = not at all, 4 = very much)
OB-child total score (Cronbach’s α = .90)	2.72 ± 1.64
Compared to other children with asthma whose parents don’t smoke, what are the chances that your child will have an asthma attack? (1 = much lower than average, 5 = much higher than average)
Compared to other children with asthma whose parents don’t smoke, what are the chances of your child’s asthma symptoms getting worse? (1 = much lower than average, 5 = much higher than average)
Compared to other children with asthma whose parents don’t smoke, what are the chances that your child will have to visit the emergency room for an asthma attack? (1 = much lower than average, 5 = much higher than average)
Compared to other children with asthma whose parents don’t smoke, what are the chances that your child will have to visit a doctor because of worsening asthma? (1 = much lower than average, 5 = much higher than average)
PV-self total score (Cronbach’s α = .90)	15.81 ± 3.65
If you continue to smoke, how likely is it that you will develop lung cancer? (1 = no chance, 7 = certain to happen)
If you continue to smoke, how likely is it that you will develop other lung diseases, like emphysema? (1 = no chance, 7 = certain to happen)
If you continue to smoke, how likely is it that you will develop heart disease? (1 = no chance, 7 = certain to happen)
PE-self total score (Cronbach’s α = .90)	10.15 ± 2.41
If you stop smoking how much do you think that would reduce your risk for developing lung cancer? (1 = no decrease in risk, 5 = complete elimination of risk)
If you stop smoking how much do you think that would reduce your risk for developing other lung disease, like emphysema? (1 = no decrease in risk, 5 = complete elimination of risk)
If you stop smoking how much do you think that would reduce your risk for developing heart disease? (1 = no decrease in risk, 5 = complete elimination of risk)
OB-self total score (Cronbach’s α = .92)	0.50 ± 1.04
Compared to the typical smoker would you say your risk for developing lung cancer is: (1 = a lot lower, 5 = a lot higher)
Compared to the typical smoker would you say your risk for developing other lung diseases, like emphysema is: (1 = a lot lower, 5 = a lot higher)
Compared to the typical smoker would you say your risk for developing heart disease is: (1 = a lot lower, 5 = a lot higher)

Note. PV = Perceived Vulnerability; PE = Precaution Effectiveness; OB = Optimistic Bias.