Comparison 1. Extended specialised early intervention versus standard specialised early intervention + treatment as usual.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1.1 Global state: recovery	3	780	Risk Ratio (IV, Random, 95% CI)	1.13 [0.97, 1.31]
1.2 Service use: disengagement from services	2	380	Risk Ratio (IV, Random, 95% CI)	0.45 [0.27, 0.75]
1.3 Service use: admission to psychiatric hospital	1	160	Risk Ratio (IV, Random, 95% CI)	1.55 [0.68, 3.52]
1.4 Service use: number of days in psychiatric hospital per year ‐ skewed data	2		Other data	No numeric data
1.5 Global state: relapse, as defined by the study	1	160	Risk Ratio (IV, Random, 95% CI)	0.82 [0.42, 1.62]
1.6 Mental state: specific, average endpoint score on specific symptoms mental state scale/subscale, general psychotic symptoms	1	156	Mean Difference (IV, Random, 95% CI)	‐1.90 [‐3.28, ‐0.52]
1.7 Mental state: specific, average endpoint score on specific symptoms ‐ skewed data mental state scale/subscale, positive psychotic symptoms	2		Other data	No numeric data
1.8 Mental state: specific, average endpoint score on specific symptoms mental state scale/subscale, negative psychotic symptoms ‐ skewed	3		Other data	No numeric data
1.9 Mental state: specific, average endpoint score on specific symptoms mental state scale/subscale, depressive symptoms ‐ skewed	1		Other data	No numeric data
1.10 Adverse effects/events: death, suicide or natural cause	3	780	Risk Ratio (IV, Random, 95% CI)	0.38 [0.09, 1.64]
1.11 Leaving the study early: for any reason	3	780	Risk Ratio (IV, Random, 95% CI)	0.58 [0.33, 1.01]
1.12 Functioning: general, average endpoint score on general functioning scale	2	560	Std. Mean Difference (IV, Random, 95% CI)	0.23 [‐0.29, 0.76]
1.13 Functioning: specific, any change in education or employment status	2	560	Risk Ratio (IV, Random, 95% CI)	1.11 [0.79, 1.56]
1.14 Satisfaction with care: recipient, average endpoint score on satisfaction scale	1	400	Mean Difference (IV, Random, 95% CI)	2.60 [1.38, 3.82]
1.15 Sensitivity analysis (assumptions for lost binary data) ‐ global state: recovery	3	596	Risk Ratio (IV, Random, 95% CI)	1.11 [0.96, 1.27]
1.16 Sensitivity analysis (assumptions for lost binary data) ‐ service use: disengagement from services	2	380	Risk Ratio (IV, Random, 95% CI)	0.45 [0.27, 0.75]
1.17 Sensitivity analysis (fixed‐effect model) ‐ global state: recovery	3	780	Risk Ratio (IV, Fixed, 95% CI)	1.13 [0.97, 1.31]
1.18 Sensitivity analysis (fixed‐effect model) ‐ service use: disengagement from services	2	380	Risk Ratio (IV, Fixed, 95% CI)	0.44 [0.30, 0.64]
1.19 Subgroup analysis (extended SEI 60 months or more) ‐ global state: recovery	2	620	Risk Ratio (IV, Random, 95% CI)	1.09 [0.86, 1.39]
1.20 Subgroup analysis (extended SEI 60 months or more) ‐ service use: disengagement from services	1	220	Risk Ratio (IV, Random, 95% CI)	0.40 [0.27, 0.61]
1.21 Subgroup analysis (extended SEI 60 months or more) ‐ service use: number of days in psychiatric hospital	1	400	Mean Difference (IV, Random, 95% CI)	‐2.70 [‐8.30, 2.90]
1.22 Subgroup analysis (extended SEI 60 months or more) ‐ mental state: specific, average endpoint score on specific symptoms mental state scale/subscale, positive psychotic symptoms	1	400	Std. Mean Difference (IV, Random, 95% CI)	‐0.15 [‐0.34, 0.05]
1.23 Subgroup analysis (extended SEI 60 months or more) ‐ mental state: specific, average endpoint score on specific symptoms mental state scale/subscale, negative psychotic symptoms	2	578	Std. Mean Difference (IV, Random, 95% CI)	‐0.03 [‐0.19, 0.14]
1.24 Subgroup analysis (extended SEI 60 months or more) ‐ adverse effects/events: death, suicide or natural cause	2	620	Risk Ratio (IV, Random, 95% CI)	0.44 [0.06, 2.99]
1.25 Subgroup analysis (extended SEI 60 months or more) ‐ leaving the study early: for any reason	2	620	Risk Ratio (IV, Random, 95% CI)	0.59 [0.29, 1.22]
1.26 Subgroup analysis (extended SEI 60 months or more) ‐ functioning: general, average endpoint score on general functioning scale	1	400	Std. Mean Difference (IV, Random, 95% CI)	‐0.02 [‐0.22, 0.18]
1.27 Subgroup analysis (extended SEI 60 months or more) ‐ functioning: specific, any change in education or employment status	1	400	Risk Ratio (IV, Random, 95% CI)	0.93 [0.66, 1.31]