Comparison 2. 5‐ASA versus sulfasalazine.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
2.1 Failure to induce global/clinical remission	8	526	Risk Ratio (M‐H, Fixed, 95% CI)	0.90 [0.77, 1.04]
2.1.1 5‐ASA / SASP < 1/2	1	29	Risk Ratio (M‐H, Fixed, 95% CI)	0.90 [0.57, 1.41]
2.1.2 1/1 > 5‐ASA / SASP ≥ 1/2	5	359	Risk Ratio (M‐H, Fixed, 95% CI)	0.91 [0.77, 1.08]
2.1.3 5‐ASA / SASP ≥ 1/1	3	138	Risk Ratio (M‐H, Fixed, 95% CI)	0.85 [0.59, 1.23]
2.2 Failure to induce global/clinical improvement (including remission)	14	1053	Risk Ratio (M‐H, Fixed, 95% CI)	0.88 [0.76, 1.01]
2.2.1 5‐ASA / SASP < 1/2	3	123	Risk Ratio (M‐H, Fixed, 95% CI)	0.77 [0.47, 1.27]
2.2.2 1/1 > 5‐ASA / SASP ≥ 1/2	11	804	Risk Ratio (M‐H, Fixed, 95% CI)	0.90 [0.77, 1.05]
2.2.3 5‐ASA / SASP ≥ 1/1	3	126	Risk Ratio (M‐H, Fixed, 95% CI)	0.81 [0.54, 1.22]
2.3 Failure to induce endoscopic improvement (including remission)	6	362	Risk Ratio (M‐H, Fixed, 95% CI)	0.82 [0.65, 1.02]
2.3.1 5‐ASA / SASP < 1/2	1	29	Risk Ratio (M‐H, Fixed, 95% CI)	0.78 [0.58, 1.04]
2.3.2 1/1 > 5‐ASA / SASP ≥ 1/2	4	246	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.53, 1.02]
2.3.3 5‐ASA / SASP ≥ 1/1	2	87	Risk Ratio (M‐H, Fixed, 95% CI)	1.06 [0.72, 1.57]
2.4 Adverse events	12	909	Risk Ratio (M‐H, Fixed, 95% CI)	0.48 [0.36, 0.63]
2.4.1 5‐ASA / SASP < 1/2	1	56	Risk Ratio (M‐H, Fixed, 95% CI)	0.35 [0.10, 1.20]
2.4.2 1/1 > 5‐ASA / SASP ≥ 1/2	9	746	Risk Ratio (M‐H, Fixed, 95% CI)	0.55 [0.41, 0.73]
2.4.3 5‐ASA / SASP ≥ 1/1	2	107	Risk Ratio (M‐H, Fixed, 95% CI)	0.16 [0.05, 0.52]
2.5 Serious adverse events	2	107	Risk Ratio (M‐H, Fixed, 95% CI)	1.36 [0.28, 6.52]
2.6 Withdrawals due to adverse events	10	640	Risk Ratio (M‐H, Fixed, 95% CI)	0.40 [0.24, 0.68]
2.6.1 5‐ASA / SASP < 1/2	2	85	Risk Ratio (M‐H, Fixed, 95% CI)	0.16 [0.02, 1.41]
2.6.2 1/1 > 5‐ASA / SASP ≥ 1/2	5	361	Risk Ratio (M‐H, Fixed, 95% CI)	0.67 [0.32, 1.39]
2.6.3 5‐ASA / SASP ≥ 1/1	4	194	Risk Ratio (M‐H, Fixed, 95% CI)	0.25 [0.10, 0.60]
2.7 Exclusions and withdrawals after study entry	10	701	Risk Ratio (M‐H, Fixed, 95% CI)	0.76 [0.58, 0.99]
2.7.1 5‐ASA / SASP < 1/2	1	29	Risk Ratio (M‐H, Fixed, 95% CI)	0.10 [0.01, 1.80]
2.7.2 1/1 > 5‐ASA / SASP ≥ 1/2	6	478	Risk Ratio (M‐H, Fixed, 95% CI)	0.97 [0.71, 1.34]
2.7.3 5‐ASA / SASP ≥ 1/1	4	194	Risk Ratio (M‐H, Fixed, 95% CI)	0.44 [0.25, 0.77]