Comparison 1. High‐dose chemotherapy versus standard chemotherapy.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Overall survival	14		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
1.1 3‐year follow‐up	3	795	Risk Ratio (M‐H, Fixed, 95% CI)	1.02 [0.95, 1.10]
1.2 5‐year follow‐up	8	3566	Risk Ratio (M‐H, Fixed, 95% CI)	1.00 [0.96, 1.04]
1.3 6‐year follow‐up	1	511	Risk Ratio (M‐H, Fixed, 95% CI)	0.94 [0.81, 1.08]
1.4 8‐year follow‐up	1	344	Risk Ratio (M‐H, Fixed, 95% CI)	1.17 [0.95, 1.43]
1.5 12‐year follow‐up	1	382	Risk Ratio (M‐H, Fixed, 95% CI)	1.18 [0.99, 1.42]
2 Event‐free survival	14		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
2.1 3‐year follow‐up	3	795	Risk Ratio (M‐H, Fixed, 95% CI)	1.19 [1.06, 1.34]
2.2 5‐year follow‐up	8	3566	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.99, 1.10]
2.3 6‐year follow‐up	1	511	Risk Ratio (M‐H, Fixed, 95% CI)	1.04 [0.87, 1.24]
2.4 8‐year follow‐up	1	344	Risk Ratio (M‐H, Fixed, 95% CI)	1.27 [0.99, 1.64]
2.5 12‐year follow‐up	1	382	Risk Ratio (M‐H, Fixed, 95% CI)	1.18 [0.95, 1.45]
3 Treatment‐related mortality	14	5600	Risk Ratio (M‐H, Fixed, 95% CI)	7.97 [3.99, 15.92]
4 Second cancers	7	3423	Risk Ratio (M‐H, Fixed, 95% CI)	1.25 [0.90, 1.73]
4.1 By median 4‐ to 5‐year follow‐up	2	817	Risk Ratio (M‐H, Fixed, 95% CI)	2.34 [0.61, 8.99]
4.2 By median 6‐year follow‐up	1	511	Risk Ratio (M‐H, Fixed, 95% CI)	1.69 [0.75, 3.78]
4.3 By median 7‐year follow‐up	3	1751	Risk Ratio (M‐H, Fixed, 95% CI)	1.02 [0.69, 1.51]
4.4 By median 8‐ to 9‐year follow‐up	1	344	Risk Ratio (M‐H, Fixed, 95% CI)	2.97 [0.61, 14.49]