HOUSTON -

A study released Tuesday reveals big city school districts with teacher attendance problems. And it could be hurting education.

The study from the National Council On Teacher Quality looked at attendance for more than 234,000 teachers nationwide during the 2012-2013 school year. It found 16 percent of teachers were considered chronically absent, because they missed 18 days or more in the school year. 

The worst offender according to the study is Columbus, Ohio, where nearly 69 percent of teachers were either frequently or chronically absent. Also high on the list:  Nashville, Tennessee, New Orleans, Louisiana, and San Antonio.

Houston is one of the districts with a lower average, with fewer than 14 percent of teachers considered chronically absent, and more than 24 percent with what's considered excellent attendance.

The report did find that, on average, public school teachers were in the classroom 94 percent of the school year. But the council is concerned about the group of teachers considered chronically absent, and the affect on student education.

The study did not include long-term absences for illness, or maternity and paternity leave.

You can read the full report here.