Table 4. Social and Program Costs per Child When Sensitivity Threshold for Externalizing Problems Is Set at.50.

True condition (%)	Screened as (%)		% of sample	Program cost ($)	Chance of becoming lifetime criminal (%)	Costs of a lifetime of crime ($)	Expected social costs ($)	Expected social costs + program cost ($)
Positive (20)	TP	50	10	20,000	15	2,000,000	300,000	320,000
	FN	50	10	0	30	2,000,000	600,000	600,000
Negative (80)	TN	90	72	0	5	2,000,000	100,000	100,000
	FP	10	8	20,000	5	2,000,000	100,000	120,000

Note. Program cost is based on data from Washington State Institute for Public Policy (1998). Chance of becoming a lifetime criminal and costs of a lifetime of crime is based on data from Cohen (1998). Expected social costs = chance of becoming lifetime criminal × costs of a lifetime of crime. The expected cost of society per child (Expected social and program costs × % of sample, summed across all four groups) is $173,600. TP = true positive; FN = false negative; TN = true negative; FP = false positive.