Table 2. Unweighted absolute risks and number needed to treat (NNT) for events of interest after 10 years of follow-up.

Event of interest	Number ofincluded studies	Absolute risk inextended adjuvanttamoxifen group	Absolute risk inadjuvant tamoxifengroup	Absolute riskdifference	NNT*
Any recurrence (all patients)	3 [6], [8], [15]	12.7%	14.5%	1.8%	57
Any recurrence (excluding ER-negative)	3 [6], [8], [15]	17.5%	20.2%	2.7%	38
Distant recurrence	1 [8]	15.0%	16.2%	1.3%	79
Death after recurrence	3 [6], [8], [15]	7.7%	8.7%	1.0%	101
Death without recurrence	3 [6], [8], [15]	11.9%	11.8%	−0.0008%	−1281
All cause death	3 [6], [8], [15]	15.4%	16.7%	1.3%	79

95% CI, 95% confidence intervals. ER, estrogen receptor.

*Negative value suggests more events in extended adjuvant group (i.e. net harm).