Table 4.

ITR effects of three non-personalized rules on the utility outcome. The trade-off parameter b in the utility function varies from 1 to 5 at an increment of 1.

	ITR Effects on Utility
Non-personalized Rule	b = 1	b = 2	b = 3	b = 4	b = 5
Recommend all male donors to donate every 12 weeks	−1.308	−0.828	−0.618	−0.408	−0.199
Recommend all male donors to donate every 10 weeks	−0.025	0.027	0.079	0.131	0.183
Recommend all male donors to donate every 8 weeks	1.055	0.795	0.535	0.275	0.015

Note: ITR effects measure the difference in the average outcome between donors whose assigned inter-donation intervals in the trial are the same as the one specified in the non-personalized rule and those whose assigned inter-donation intervals are different from that specified in the non-personalized rule. A larger ITR effect on utility is more desirable.