Article type
Year
Abstract
Introduction:
Objectives: To compare the results of randomized trials and observational studies of interventions to prevent adolescent pregnancy.
Methods: Data Source: We identified published and unpublished reports through computerised searches of 11 electronic data bases; manual searches of eight relevant journals; reference lists from primary articles; and contact with content experts. Study Selection: We included randomized trials and observational studies that evaluated the impact of primary prevention interventions on three outcomes: sexual intercourse, birth control use, or pregnancy in adolescents. Data Extraction: One investigator abstracted the data and a second conducted a detailed review of the abstraction.
Results: We identified 13 randomized trials and 17 observational studies. We generated estimates of the impact of the interventions separately for males and females for all three outcomes for both observational studies and randomized trials. For four of the six outcomes the summary odds ratios for the observational studies showed a significant intervention benefit (p<0.05) while the randomized trials did not show a benefit for any outcome in either females or males. The difference between the results of the observational studies and randomized trials was statistically significant in two of the six outcomes (p<0.05 for initiation of intercourse and pregnancy in females).
Discussion: Observational studies yield systematically greater estimates of treatment effects than randomized trials of adolescent pregnancy prevention interventions.
Objectives: To compare the results of randomized trials and observational studies of interventions to prevent adolescent pregnancy.
Methods: Data Source: We identified published and unpublished reports through computerised searches of 11 electronic data bases; manual searches of eight relevant journals; reference lists from primary articles; and contact with content experts. Study Selection: We included randomized trials and observational studies that evaluated the impact of primary prevention interventions on three outcomes: sexual intercourse, birth control use, or pregnancy in adolescents. Data Extraction: One investigator abstracted the data and a second conducted a detailed review of the abstraction.
Results: We identified 13 randomized trials and 17 observational studies. We generated estimates of the impact of the interventions separately for males and females for all three outcomes for both observational studies and randomized trials. For four of the six outcomes the summary odds ratios for the observational studies showed a significant intervention benefit (p<0.05) while the randomized trials did not show a benefit for any outcome in either females or males. The difference between the results of the observational studies and randomized trials was statistically significant in two of the six outcomes (p<0.05 for initiation of intercourse and pregnancy in females).
Discussion: Observational studies yield systematically greater estimates of treatment effects than randomized trials of adolescent pregnancy prevention interventions.