There’s an ongoing debate about how we should evaluate the effectiveness of school choice policies. Last month, two education professors argued that standardized test scores should be “the measure of success.” Other education researchers – including myself – contend that we should take a more holistic approach by looking at other relevant long-term outcomes as well. After all, schools can do so much more than shape test scores. Here’s a case in point.

A just-released evaluation found that a school choice program Colombia improved vital long-run outcomes up to 20 years after students applied for private school vouchers in 1994.

The research team, led by Stanford University’s Eric Bettinger, found that winning a lottery to use a voucher to attend a private school in 6th grade increased earnings by 8 percent overall and 11 percent for females by the time the students reached around 33 years of age. In other words, it looks like school choice could help close the gender wage gap in Colombia. The program also increased adult earnings by 17 percent for students who applied to vocational schools.

Higher earnings should be enough to demonstrate this voucher program’s success. But don’t drop the mic just yet.

The study also found that winning the voucher lottery reduced the likelihood of having a child as a teenager by 18 percent. Voucher lottery winners were also 17 percent more likely to complete secondary school on time and 13 percent more likely to enroll in tertiary education than the control group. The authors also reported that these long-run gains “occur at a low or possibly negative cost to taxpayers,” implying the program has a positive return on investment.

We should consider all relevant outcomes when evaluating any education policy, especially since families don’t want schools solely focusing on standardized tests. Families want schools to help their children succeed in life. And it looks like private schools in Colombia are doing just that.