Rationale:

1. Sum threat score and efficacy score separately.

2. Subtract threat score from efficacy score, yielding a critical value.

3. If value is positive, indicates that efficacy is stronger than threat, and person is in danger control. Messages can focus on increasing perceptions of severity and susceptibility (with appropriate efficacy messages), to increase behavior change.

4. If value is negative, indicates that threat is stronger than efficacy, and person is in fear control. Messages must focus on efficacy only (because people are already too scared).