A recent study has challenged the use of a new “values-added” evaluation system for teachers, under which districts across the country depend on standardized test scores to monitor teacher performance.

In most instances, teachers who fail to pass muster get the boot, as in Washington, D.C. this summer where more than 200 public schools educators who lost their jobs.

The 29-page report, titled “Problems with the Use of Student Test Scores to Evaluate Teachers” and conducted by the Washington, D.C.-based Economic Policy Institute, found that test scores also hinge on factors such as student attendance, peer interaction and home experiences.

According to the report, if scores remain central in determining performance, more teachers could lose their jobs—but with no guarantee they’d be replaced by more effective recruits. The study concluded, in part, that there is no perfect method for evaluating teachers.

Randi Weingarten, president of the American Federation of Teachers, along with U. S. Secretary of Education Arne Duncan and D. C. schools Chancellor Michelle Rhee participated this week in an ABC News debate on teacher evaluations.

“Failure is not an option and I think that what’s happened is that we’re all trying to figure out…how to make teaching into an art and a science, which is why data is really important,” Weingarten said.

Duncan added that, while teachers want to get better, districts, unions and education stakeholders have to work together to help empower them. “This should be a piece to how teachers are evaluated,” Duncan said, “as we have to look at multiple measures.”

Rhee said Washington D.C. has revamped its evaluation model so that it was more aligned with both teacher and student performance.

“In our new model, 50 percent of the evaluation is based on how much are progressing and students’ academic achievement level ,” Rhee said. “Forty percent is based on observation of classroom practice, another 5 percent is based on how well the school is doing overall, and the final 5 percent is based on contribution to the school community.”