Comparison 1. Ketamine versus placebo.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Response rate	2		Odds Ratio (M‐H, Random, 95% CI)	Subtotals only
1.1.1 at 24 hours	2	33	Odds Ratio (M‐H, Random, 95% CI)	11.61 [1.25, 107.74]
1.1.2 at 3 days	2	33	Odds Ratio (M‐H, Random, 95% CI)	8.24 [0.84, 80.61]
1.1.3 at 1 week	1	18	Odds Ratio (M‐H, Random, 95% CI)	4.00 [0.33, 48.66]
1.2 Remission rate	2		Odds Ratio (M‐H, Random, 95% CI)	Subtotals only
1.2.1 at 24 hours	2	33	Odds Ratio (M‐H, Random, 95% CI)	5.16 [0.51, 52.30]
1.2.2 at 3 days	2	33	Odds Ratio (M‐H, Random, 95% CI)	3.62 [0.34, 38.60]
1.2.3 at 1 week	1	18	Odds Ratio (M‐H, Random, 95% CI)	3.35 [0.12, 93.83]
1.3 Depression rating scale score	2		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
1.3.1 at 24 hours	2	32	Mean Difference (IV, Fixed, 95% CI)	‐11.81 [‐20.01, ‐3.61]
1.3.2 at 3 days	2	31	Mean Difference (IV, Fixed, 95% CI)	‐9.10 [‐16.00, ‐2.21]
1.3.3 at 1 week	2	28	Mean Difference (IV, Fixed, 95% CI)	‐0.88 [‐5.88, 4.12]
1.3.4 at 2 weeks	2	26	Mean Difference (IV, Fixed, 95% CI)	‐1.14 [‐6.30, 4.01]
1.4 Acceptability ‐ total dropouts	2	33	Odds Ratio (M‐H, Random, 95% CI)	3.48 [0.56, 21.74]
1.5 Acceptability ‐ lack of efficacy	2	33	Odds Ratio (M‐H, Random, 95% CI)	5.65 [0.76, 41.87]