Table 2. Estimated costs and health outcomes over the trial period^a.

Outcome	Estimated meanb (SE)		Mean difference
	IERITAc plus TAUd (n=84)	TAU only (n=82)	Unadjustede	Adjusted (95% CI)f
1-month posttreatment
Costs (US $)
Health care costs	7658 (238)	3926 (241)	3733g	3663 (2182 to 5002)
Societal costs	23,758 (953)	18,265 (965)	5493g	4458 (−577 to 9509)
Health outcomes
NSSIh frequency	1.29 (95% CI 0.94 to 1.63)	2.21 (95% CI 1.87 to 2.54)	0.92i	N/Aj
NSSI remission	0.61 (0.02)	0.38 (0.02)	0.23g	0.23 (0.08 to 0.39)
QALYsk	0.205 (0.01)	0.199 (0.01)	0.006g	0.005 (0.001 to 0.01)
3-months posttreatment
Costs (US $)
Health care costs	9649 (320)	6126 (324)	3524g	3440 (1455 to 5319)
Societal costs	34,559 (1402)	28,328 (1419)	6231l	4565 (−2820 to 11,919)
Health outcomes
NSSI frequency	1.17 (95% CI 0.88 to 1.46)	1.68 (95% CI 1.30 to 2.06)	0.51i,m	N/A
NSSI remission	0.58 (0.02)	0.51 (0.02)	0.07m	0.06 (−0.10 to 0.21)
QALYs	0.313 (0.002)	0.302 (0.002)	0.010g	0.009 (0.001 to 0.017)

^aCosts and QALYs are accumulated from baseline until follow-up, NSSI frequency shows estimated values from baseline to follow-up and NSSI remission shows between-group differences at follow-up.

^bEstimated means from the multiply imputed datasets.

^cIERITA: internet-delivered emotion regulation individual therapy for adolescents.

^dTAU: treatment as usual.

^eP values not adjusted for multiple testing.

^fAdjusted mean differences from 5000 bootstrap samples while controlling for baseline costs in the same category (costs) or baseline CHU9D utilities. No adjustment for NSSI remission differences.

^gP<.001.

^hNSSI: nonsuicidal self-injury.

ⁱIncidence rate ratio=0.92 (95% CI 0.88-0.91); P<.001. Values indicate the estimated reduction in NSSI frequency of IERITA plus TAU compared to TAU only.

^jNot applicable.

^kQALY: quality-adjusted life year.

^lP<.01.

^mP<.05.