Noncredit short-term programs at community colleges yield modest earnings gains for students and increase their likelihood of employment, but gains vary based on field and gender differences, according to a new study published in Educational Evaluation and Policy Analysis, a journal of the American Educational Research Association.

The study, conducted by researchers at the Strada Institute for the Future of Work and E&E Analytics, tracked the earnings and employments of more than 128,000 students who enrolled in noncredit job training courses at Texas community colleges between fall 2011 and fall 2014, using administrative data from the Texas Higher Education Coordinating Board and the Texas Workforce Commission.

The study found that within two years of completing a job-training program, graduates earned about $2,000 more per year on average. These workers were also four percentage points more likely to be employed than peers who didn’t participate in such programs. The average earnings gain per year jumped to $4,000 when accounting for workers who were unemployed before enrolling in these occupational programs.

But program outcomes varied widely by field and duration, according to the study. For example, programs in transportation, construction or engineering technology fields saw high returns, while students in business and information sciences programs experienced little to no gains. Longer programs, more than 150 hours, also tended to yield the highest earning increases.

Co-author Peter Riley Bahr, vice president of employer alignment at Strada Education Foundation and managing research director of the Strada Institute for the Future of Work, said in a news release that more research is needed to understand “the extent of alignment between training and employment opportunities across fields of study, and how these dynamics shape wage outcomes.”

The study also found men had stronger long-term earnings gains on average than women in these programs. Men also experienced earnings gains of similar amounts in training programs whether they were employer-sponsored or not, whereas women had significantly higher gains in employer-sponsored programs and next to no gains in other programs on average.

“Average gains for women are a fraction of the gains for men, and the gap doesn’t appear to be entirely a result of difference in the fields of study that men and women tend to choose,” Bahr said in the release. “There seem to be distinct gender dynamics at play in noncredit training and related workforce opportunities, which need to be investigated more closely.”