Table 1.

Attributes and levels used in the discrete choice experiment

Attribute	Levels
1. Your doctor's estimate of risk of cancer returning (without using a GEP test)	Low risk of cancer returning (eg, lymph node negative, the cancer is not responsive to Herceptin, the cancer is highly responsive to hormone therapy, tumour size is between 1.1 and 2.0 cm) Intermediate risk of cancer returning (eg, lymph node negative, the cancer is not responsive to Herceptin, the cancer is less responsive to hormone therapy, tumour size is between 2.1 and 3 cm) High risk of cancer returning (eg, lymph node negative, the cancer is responsive to Herceptin, the cancer is less responsive to hormone therapy, tumour size is between 3.1 and 5 cm)
2. Trust in your cancer treatment doctor	Do not trust Somewhat trust Totally trust
3. Likelihood of temporary side effects (may commonly occur during chemotherapy—may include nausea, vomiting, numbness or tingling in fingers, hair loss, fever and infection)	Low Moderate High
4. Likelihood of permanent side effects (may occur after chemotherapy and last permanently—may include leukaemia (blood cancer), damage to the heart muscle and early menopause)	Low Moderate High
5. GEP test score Likely benefit from chemotherapy	9, Low benefit 22, Uncertain benefit 44, High benefit GEP test not available

GEP, gene expression profiling.