Table 1.

Characteristics of included trials

ID	Authors	Date	Design	Intervention	Control	Participant characteristics	Sample size	Outcomes measured	Effect size (d)
1	Alzua, Cruces, & Lopez-Erazo [30]	2013	Exp	Entra21 Classroom Internship Basic skills 884 h	No contact	Argentinian Below poverty line Unemployed 18–30 $\overline{x}\mathrm{age}$ = 23.55 (I), 23.80 (C) 33% male	407 randomised. 407 analysed.	Employment status Receipt of welfare Credit standing N credit enquiries	.154 – – –
2	Attanasio, Kugler, & Meghir [29]	2011	Exp	Jóvenes en Acción Classroom On-the-job 6 months, 5 h per day	Wait-list	Columbian Unemployed Lowest deciles of income distribution/Poor youth in urban areas $\overline{x}\mathrm{age}$ = 21.1 (I), 21.22 (C) 44.4%male	4353 randomised 3549 analysed.	Employment status Earnings
3	Bloom, Orr, Cave, Bell, & Doolittle [33]	1993	Exp	JTPA II-A Classroom On-the-job Other services 3–5 months	Some received classroom training only.	USA Economically disadvantaged, facing barriers to employment. 45% male $\overline{x}\mathrm{age}$ = 19	4793 randomised. 4048 analysed.	Employment status Earnings Achieved HSD or GED
4	Borland, Tseng, & Wilkins [31]	2013	Exp	YP4 Case management 23 meetings, 2 years	Standard service delivery	Australian Homeless (or history of homelessness/disadvantage) job seekers 18–35 $\overline{x}\mathrm{age}$ = 23.34 (I), 22.92 (C)	445 recruited. 208-355 analysed.	Employment status N days income support Receipt of welfare DEEWR programme expenditure Health and Wellbeing Community activities Housing
5	Borland, & Tseng [34]	2007	Quasi	Job seekers diary Work search verification Fortnightly, 3 months	Standard service delivery	Australian 18–24	54,923 analysed (whole sample).	Receipt of welfare
6	Card, Ibarrarán, Regalia, Rosas-Shady, & Soares [35]	2011	Exp	Juventud y Empleo Basic skills Internship 350 h	Not specified	Dominican Republic 44.5% male Lowest income members of working age population	5723 realised treatment group, 1623 realised control group.	Employment status Earnings
7	Cave, Bos, Doolittle & Toussaint [28]	1993	Exp	Jobstart Basic skills Occupational training 800 h, 6.6 months	400 hours, not Jobstart.	USA Economically disadvantaged School drop-outs Low skilled 17-21 53.5% male	2312 randomised. 1491 analysed.	Employment status Earnings Receipt of welfare Receipt of education Receipt of qualification Pregnancy Criminal activity
8	Chen [36]	2013	Exp	Job Corps Academic Vocational Social skills 8 months residential	Wait list (3 years)	USA Disadvantaged Low income household 16–24 $\overline{x}\mathrm{age}$ 18.42 (I), 18.38 (C)	15,386 analysed.	Employment status Earnings(weekly) Receipt of welfare
9	Creed, Machin, & Hicks [37]	1996	Quasi	Youth Conservation Corps Work experience Classroom training 16 weeks	Wait list	Australian Unemployed >6 months 67% male (I), 52% (C) $\overline{x}\mathrm{age}$ = 18.76 (I), 18.71 (C)	245 randomised. 82 analysed.	Self-esteem Psyc. distress
10	Creed, Machin, & Hicks [38]	1999	Quasi	Unnamed Work experience 6–12 months	Wait list	Australian 54% male $\overline{x}\mathrm{age}$ = 19 Unemployed ≥12 months Eligible for government sponsored programmes	65 randomised. 32 analysed at F3.	Psyc. distress Self-esteem
11	Donovan, Oddy, Pardoe, & Ades [39]	1986	Quasi	Youth Opportunity Programme Work experience6–12 months	Did not access programme; unemployed.	UK $\overline{x}\mathrm{age}$ = 15.93 at T1 65% male	81 analysed.	Health status
12	Stafford [40]	1982	Quasi	Youth Opportunity Programme Work experience 6–12 months	Did not access programme; unemployed.	UK 16–18 54% male	133 analysed.	Health (GHQ)
13	Mounsey [41]	2002	Quasi	Youth training scheme Further education Placements On-the-job Duration not stated	No treatment; matched.	UK 16–17 at T1	Varied by analysis: 972 to 8885.	NEET status Expected earnings and reservation wages
14	Nafilyan, & Speckesser [42]	2014	Quasi	Youth Contract Individually tailored support 12 months est.	Matched (counterfactual); same educational attainment and probability of receiving intervention.	UK 16–18	11,144 received intervention.	NEET status
15	Schochet, McConnell, & Burghardt [43]	2003	Exp	Job Corps Educational Vocational Counselling Placements 8 months residential	Other services; not Job Corps.	USA Disadvantaged—living in a household that receives welfare or is below the poverty line, and living in an environment that impairs prospects for participating in other programmes. Free of serious behavioural and medical problems. 60% males>70% members of racial or ethnic minoritygroups 16–24	15, 406 randomised. 11,313 analysed.	Employment status Earnings
16	Schochet, Burghardt, & Glazerman [44]	2001	Exp	Job Corps Educational Vocational Counselling Placements 8 months residential	Other services; not Job Corps.	As trial 15	15, 406 randomised. 11,313 analysed.	Employment status Earnings Receipt of welfare Receipt of education Health status Criminal activity
17	Tanner, Purdon, D’Souza, & Finch [32]	2009	Quasi	Activity Agreement pilots One-to-one support Individually tailored contract Financial incentives 15 weeks	Standard service delivery; matched from non-participating areas.	England 58% males 16–17 NEET for >20 weeks Not receiving JSA.	1018 analysed at F1, 229 analysed at F2.	Education and employment Confidence and independence
18	Grace & Gill [45]	2014	Quasi	YP4 Case management 23 meetings, 2 years	Standard service delivery	Australian Homeless (or history of homelessness/disadvantage) Job seekers 18–35	422 assigned, 370 analysed.	Earnings Welfare receipt Housing