A professor co-authored a study that documents interactions between black men and law enforcement, and found that more than half experienced police discrimination within the past five years.

Lisa Bowleg, a professor of applied social psychology, co-authored the paper, which was published last month in Cultural Diversity and Ethnic Minority Psychology, an American Psychological Association journal, according to a University release.

For the study, researchers developed a questionnaire called the Police Law Enforcement Scale, which consisted of eight questions about people’s encounters with law enforcement, according to the release.

Researchers received data from 1,264 black men in Georgia of various socioeconomic, regional and legal backgrounds through computer assisted, phone-based interviews. The majority of the interviewees said they experienced police discrimination several times per year, according to the release.

The authors said police-based discrimination should be considered a public health threat after the study found the discrimination was associated with symptoms of depression, according to the release.

“It’s of the utmost importance for those of us who do research and work on black men’s health to understand black men’s experiences from their vantage point and how factors in the social environment shape mental and physical health,” Bowleg said.