Among unemployed or underemployed black youths in urban South Africa, "we show that assessing workseekers’ skills and communicating the assessment results to both workseekers and firms increases assessed workseekers’ employment by 17% (5 percentage points), earnings by 34%, and hourly wages by 20%"

https://openknowledge.worldbank.org/handle/10986/34276

Criteria: According to their list of research reports. Even a shallow review would count. https://www.givewell.org/research/research-on-programs.