APPENDIX.
Fatal Disease and Cancer Treatment Problems
| Fatal Disease Problem (Wang, Simons, & Brédart, 2001) |
| Positive Frame: |
| Imagine that the entire human population on the earth (i.e., approximately 6 billion people) is infected by a fatal disease. Without treatment they will die. Two alternative medical plans to treat the disease have been proposed. Assume that the exact scientific estimates of the consequences of the plans are as follows: |
| —If plan A is adopted, 2 billion people will be saved. |
| —If plan B is adopted, there is a one-third probability that all 6 billion people will be saved and two-thirds probability that none of them will be saved. |
| Which plan would you prefer? |
| Negative Frame: |
| Imagine that the entire human population on the earth (i.e., approximately 6 billion people) is infected by a fatal disease. Without treatment they will die. Two alternative medical plans to treat the disease have been proposed. Assume that the exact scientific estimates of the consequences of the plans are as follows: |
| —If plan A is adopted, 4 billion people will die. |
| —If plan B is adopted, there is a one-third probability that none of them will die and two-thirds probability that all 6 billion people will die. |
| Which plan would you prefer? |
| Cancer Treatment Problem (McNeil, Pauker, Sox, & Tversky, 1982) |
| Both Treatment A and Treatment B are medications that are administered to a patient hospitalized for cancer. Both are given intravenously and neither one has significant side effects. Treatments A and B are considered equal except in their survival rates. |
| Positive Frame: |
| Of 100 people having Treatment A, 90 will survive during treatment; 68 will have survived by 1 year and 34 will have survived by 5 years. |
| Of 100 people having Treatment B, 100 will survive during treatment; 77 will survive by 1 year and 22 will survive by 5 years. |
| Which treatment would you prefer? |
| Negative Frame: |
| Of 100 people having Treatment A, 10 will die during treatment; 32 will have died by 1 year and 66 will have died by 5 years. |
| Of 100 people having Treatment B, none will die during treatment; 23 will die by 1 year and 78 will die by 5 years. |
| Which treatment would you prefer? |