The effectiveness of three substance abuse prevention videotapes derived fr
om contrasting theoretical frameworks war experimentally evaluated on commo
n prevention outcomes and measures of theoretical relevance. Seventh and ei
ghth graders were stratified on gender and classroom before being randomly
assigned to experimental and control conditions. In a modified replication,
ninth graders were assessed and treated in a concentrated time span. Parti
cipants were 312 students. A series of 2 x 2 x 4 (Replication x Gender x Tr
eatment) ANCOVAs permitted an inspection of the construct validity of emerg
ing effects. Although the assertion-training video produced significantly h
igher levels of assertiveness among ninth graders, the other two videos (de
rived from information-programming and help-seeking rationales) did not reg
ister effects on specific measures of high theoretical relevance, A lack of
posttest differences on the common outcomes may be due to low intended con
sumption levels displayed by participants and/or floor and ceiling effects
encountered on outcome measures.