Table VI.

Fraction of maximum possible lives saved that is achieved by allocating mammograms according to estimated breast cancer risk when there is only enough money to give mammograms to half the population.^*

Risk assessment model	AUC	Fraction of lives saved	Percent improvement
None (random allocation)		0.500
BCRAT	0.607	0.632	26.4%
BCRAT+7SNPs	0.632	0.667	33.4%
Perfect model	1.000	1.000	100.0%

^*Abbreviations: BCRAT=Breast Cancer Risk Assessment Tool; BCRAT+7SNPs = model that includes BCRAT and 7 single nucleotide polymorphisms that are associated with breast cancer; AUC= area under curves such as those in Figure 1. Fraction of lives saved is the ratio of lives saved with the risk assessment strategy to the lives that could have been saved if the entire population received mammography. Percent improvement is 100 times (fraction of lives saved minus 0.5)/0.5. In these calculations, the cost ratio of risk assessment to mammograms is assumed to be k=0.02. Data from [50].