?is study was conducted to determine the effectiveness of an HIV/AIDS educational intervention on adolescents’
knowledge about and perceptions of susceptibility and severity of HIV/AIDS. We also examined whether providing information
about assertiveness skills led to an intention to delay initiation of sexual activity. Methods. A quasi-experimental design was used
to conduct this study among secondary school students in Trinidad and Tobago. ?e ?ve constructs of the Health Belief Model
were used to design and test the impact of the educational lessons for the intervention group while the comparison group watched
one educational video about HIV over four sessions. A total of 196 secondary school students (from nine schools) between the
ages of 11 and 18 years participated in the study, 92 in the intervention group and 104 in the comparison group. Results. ?ose
in the comparison group had higher knowledge scores at posttest than the intervention group, controlling for pretest knowledge
(???? ?? ????????), but those in the intervention group were more likely to plan to delay sexual initiation (???? ?? ????????). Conclusions. While
knowledge scores increased for both groups, intention to delay sexual intercourse was only seen among the intervention group and
within the younger age groups.