Train the Trainer Course book - Cochrane Public Health Group

intercourse. Pooled odds ratio 0.99 (95% CI 0.84
to 1.16).
2) Use of birth control
Every time they had intercourse (Fig 2)
Young women: 8 studies of 1967 women
showed no improvement in use of birth control
at every intercourse (0.95; 0.69 to 1.30). There
was significant heterogeneity among studies
(p=0.08). Unexplained heterogeneity.
Young men: 3 studies of 1505 young men
indicated that the programmes did not improve
the use of birth control at every intercourse
(0.90;0.70 to 1.16). Heterogeneous studies.
Use of birth control last time they had
intercourse (Fig 3)
Young women: 5 studies of 799 young women
showed no improvement (1.05;0.5 to 2.19) with
significant heterogeneity, p=0.007).
Heterogeneity not explained by hypotheses.
Young men: 4 studies of 1262 young men
showed no improvement (1.25;0.99 to 1.59), no
heterogeneity.
3) Pregnancy
Young women: 12 studies of 8019 young women
showed that the interventions did not reduce
pregnancy rates (1.04;0.78 to 1.4), no
heterogeneity.
Young men – pregnancies with partners – 5
studies of 3759 young men showed no effect of
interventions on reducing pregnancies among
partners of young men, (1.54;1.03 to 2.29), no
heterogeneity.
7. Could these results be due to chance?
HINT: Look for tests of statistical significance eg. p
values and confidence intervals (CIs)
8. Can the results be applied to the local
population?
HINT: Consider whether
- the population sample covered by the
review could be sufficiently different to your
population to cause concern.
– your local setting is likely to differ much
from that of the review
Most results are not significant. The only
significant difference was for pregnancies in
partners of young men, CI (1.54;1.03 to 2.29).
Confidence interval does not include one, the
null hypothesis.
Most of the participants in over half of the
studies were African-American or Hispanic,
thus over-representing low socioeconomic
groups.
Interventions may be more successful in other
populations.
In all but 5 studies, participants received
conventional sex education in the control group.
It is possible that these interventions had some
effect, and tested interventions were not potent
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