This should be comforting to parents with a child who depends on medication for Attention Deficit Disorder. A new study finds that kind of drug use does not contribute to drug abuse later in life. The study followed both kids who took stimulant drugs and those who took no medication for 13 years. Researchers say they found no real difference in drug use among either of those groups. The study is published in the journal "Pediatrics." The study was conducted by researchers at Massachusetts General Hospital and the University of Wisconsin at Madison.