Study leader Jeffrey Wood of the University of California, Los Angeles, said the longitudinal study involved more than 17,000 students in grades 1 through 12, using three data sets -- adolescents in grades seven to 12; children in grades one to eight; and youths in grades one through 12.
Wood and colleagues at the University of Florida, Boston University, the Child and Adolescent Services Research Center in San Diego, the Oregon Social Learning Center and Johns Hopkins University found between grades two to eight, students who already had mental health symptoms such as anti-social behavior or depression missed more school days during the course of a year than they had in the previous year, and more than students with few or no mental health symptoms.
Conversely, middle- and high-school students who were chronically absent in an earlier year of the study tended to have more depression and anti-social problems in subsequent years, Wood said.
For example, students in grade eight who were absent more than 20 days were more likely to have higher levels of anxiety and depression in 10th grade than were eighth-graders who were absent fewer than 20 days, the study said.
The study was published in the journal Child Development.