Current guidelines for predicting depression diagnosis aren't as effective when used to determine depression among African Americans, a new study suggests. Researchers recently discovered that the standard ways of predicting depression risk are not as effective among African Americans when compared to their Caucasian counterparts.

Researchers from the University of Michigan Medical School and School of Public Health looked at data from 2,205 Caucasians and 1,156 African Americans. All participants took a standard depression screening test at the beginning of the study. The screening test included various questions on participants' emotions, sleep, appetite and energy levels.

Participants were called back into the lab 15 years later to undergo extensive interviews on their mental health.

"Black-White differences are shown in psychosocial and medical correlates of depressive symptoms and major depressive disorder (MDD). The current longitudinal study compared Blacks and Whites for the association between baseline depressive symptoms and subsequent risk of MDD after 15 years," researchers wrote in the study.

Researchers were surprised to find that the early questionnaire was significantly more effective in predicting depression symptoms among Caucasians compared with African Americans. Researchers noted that the latest findings held true even after accounting for social, economic and physical health status.

"Counting the number of symptoms does not similarly inform us about the subsequent risk of the clinical disorder similarly for whites and blacks," study author Shervin Assari, of the University of Michigan Department of Psychiatry, said in a university release.

"This finding questions the universal applicability of a tool which has been developed and validated for whites. The results also have major implications for screening and treatment of depression in black communities," Assari explained.

"Black-White differences exist in the association between baseline depressive symptoms and subsequent risk of MDD >15 years. Ethnic differences in the longitudinal link between baseline CES-D and subsequent risk of MDD may explain some of the Black-White differences in social, psychological, and medical correlates of depressive symptoms and depression. Future research is still needed to compare Blacks and Whites for factor structure of the CES-D," the researchers concluded.

The findings were published online in Frontiers in Public Health.