Taking remedial courses may not help students earn bachelor's degrees, according to a recent study.

Researchers from Boston College's Lynch School of Education found that remedial courses at four-year colleges may hold students back from earning bachelor's degrees, but may benefit students trying to earn an associate's degree.

"The role of remedial education has been under scrutiny for years, viewed as an essential tool in efforts to raise rates of degree completion," researchers said in a statement. "At the same time, critics question whether the courses are appropriate for institutions of higher education."

For the study, researchers reviewed a federal database of interviews and academic transcript data from more than 10,000 students at 670 two- and four-year institutions.

They found that at four-year colleges, students who took three or more remedial courses struggled to attain a bachelor's degree when compared to similar peers who took no remedial courses. Among students at two-year colleges, taking developmental education courses was associated with better odds of earning an associate's degree "but no higher within six years of enrollment," researcher Katherine A. Shields said.

When researchers compared the relationship of taking remedial courses to the chances of two-year college students ultimately earning a bachelor's degree, the potential benefits of the courses disappeared.  Based on their findings, taking three or more remedial courses at the two-year college level was negatively associated with attaining a bachelor's degree.

Researchers concluded that developmental education may divert them from transferring to complete a higher degree.

The results show that remedial education at the two-year level is not a hindrance in the same way as it seems to be at the four-year level, but more research is needed to determine which types of programs are the most effective and why.

"We need further investigation of the ingredients for success at those colleges where taking developmental coursework doesn't hold students back from finishing an associate's degree," Shields said.