THE KITCHEN SINK: COMBINING MULTIPLE RISK COMMUNICATION STRATEGIES TO CONVEY MULTIPLE DISEASE RISKS

Purpose:

  Even though a single risk factor can affect the risk of multiple diseases, this information is seldom communicated in a way that optimizes people’s understanding of the importance of engaging in a single healthy behavior. This study investigated which combination of four risk communication strategies most effectively conveys risk estimates of five diseases associated with physical inactivity (i.e. colon cancer, breast cancer, stroke, diabetes, heart disease).

Method:

  Participants (N=835) age 30-65 were recruited from the GfK KnowledgePanel.  Recruitment was stratified so that at least 50% of the sample had no more than vocational-technical training and 50% were racial/ethnic minorities. Participants viewed hypothetical risk calculator results.  All five diseases were placed at varying heights on a vertical bar chart (i.e., “risk ladder”) to indicate their respective probabilities.  Participants were randomly assigned to one of 12 risk communication strategies in a 2 (numerical format: numbers/words) x 2 (risk reduction information: present/absent) x 3 (social comparison information: none/somewhat higher than average/much higher than average) full factorial experimental design. The primary outcomes were risk comprehension and intentions.  Secondary outcomes were risk-related cognitions (i.e. response-efficacy, self-efficacy, severity, cognitive perceived risk, information acceptance), affect (i.e. worry, anticipated regret, affective perceived risk), and defensive processing. Data were analyzed using ANCOVAs and logistic regressions.

Result:

  None of the experimental variables influenced the primary outcomes, and there were few effects on secondary outcomes. However, information acceptance was higher among (1) people who did (vs. did not) receive risk reduction information (p=.03), and (2) people who did not receive social comparison information (vs. those told that they were at somewhat higher than average risk) (p=0.01). Social comparison had several two or three-way interactions with numerical format and risk reduction to affect severity (p=0.01), cognitive perceived risk (p=0.04), and some defensive processing scales (p’s ≤.03).

Conclusion:

  With rare exceptions, no evidence was found for the direct effects of the multiple risk communication strategies on cognitions, affect, defensive processing, and intentions to exercise. It could be that the effect of the risk ladder outweighed the effects of the different strategies, particularly for the large proportion of underserved people in this study. Moreover, the interactions suggest that combining all three strategies may induce defensiveness, especially among people told they are at much higher than average risk.