A sample of 212 youths over 6 years with assessments of SI, CDBs, and TRHPs was followed at 2, 4, and 6 years post baseline. It was hypothesized that SI and CDB would be associated with an increased incidence of TRHPs and that males would exhibit more SI and CDB than females. The independent and combined impact of SI and CDB on TRHP were also examined. The primary finding of this study was that, for males, CDB was clearly associated with the incidence and severity of TRHP during adolescence. It was also found that, for females, SI during early to middle adolescence was an important factor in the likelihood of TRHP emerging during adolescence. CDB, while not a consistent predictor, may also be implicated with TRHP. These results demonstrate that the presumed relationship between substance use and traumatic injury may be due to factors such as CDB, delinquency, and other related risk behaviors, especially for males. Problem behaviors such as SI and CD frequently co-occur, and were correlated in this study. The hypothesis was partially supported for females, as several measures were predictive of cumulative TRHP, while the pattern of CDB was weak or at best moderate for females. Contrary to the hypotheses, SI in adolescence did not predict TRHP for males. Instead, TRHP appeared to be more closely associated with risks of conduct disorder type behaviors, which were also associated with SI. Actual risk behaviors, rather than substance-related impairments, appear to lead directly to injury and subsequent health problems for young men. 4 tables, 47 references