A Randomized Trial to Test Personalized Environmental Report Back to Reduce Lung Cancer Risk.

BACKGROUND: More radon-related lung cancers occur among those exposed to tobacco smoke.

OBJECTIVES: To test the effects of a personalized environmental report back intervention on change in stage of action for air nicotine testing and adopting a smoke-free home and radon testing and mitigation from baseline to 3 months postintervention.

METHODS: The study design used a two-arm parallel groups randomized controlled trial with stratified quota sampling. The treatment group received free air nicotine and radon home test kits and a brief problem-solving phone intervention; the control group received a coupon for free test kits. A sample of 515 homeowners were enrolled; 319 completed the 3-month follow-up. Stage of action to test and remediate the home was measured consistent with the precaution adoption process model. Linear mixed modeling assessed whether the main and interaction effects of treatment and time were associated with the testing and remediation outcomes; multiple covariates were included in the models.

RESULTS: The models for the four stages of action outcomes (testing and remediating for radon and secondhand smoke) each had a significant treatment-by-time effect. The general pattern was an increase in stage of action from baseline to 3 months. The degree of change was generally larger among the treatment group participants relative to the controls, indicating that those in the treatment group were more ready to take action. For all the models, participants with higher self-efficacy for radon/air nicotine testing and radon/secondhand smoke remediation were more ready to take action to test and remediate. Synergistic risk perception was associated with stage of action for radon mitigation.

CONCLUSIONS: Homeowners who were provided free radon and air nicotine test kits, given their results, and engaged in a brief telephonic problem-solving consultation tended to show a greater increase in readiness to take action to test and remediate by 3 months compared with those who received standard public health practice. Both groups showed an increase in stage of action for all four outcomes over time.