Strategies for communicating contraceptive effectiveness: A systematic review

Knowledge of contraceptive effectiveness is crucial to making an informed choice. The consumer has to comprehend the likelihood of pregnancy and factors that influence effectiveness. We reviewed randomized controlled trials comparing strategies for communicating contraceptive effectiveness. Reports were also examined for any theoretical basis of the interventions. We searched computerized databases and wrote to known investigators for published or unpublished trials. Trials were included if they compared methods for communicating contraceptive effectiveness to consumers. The comparison could be usual practice or an alternative to the experimental intervention. For dichotomous variables, the Peto odds ratio was calculated. For continuous variables, the weighted mean difference was computed. Five trials met the inclusion criteria. In one study, knowledge gain favored a slide-and-sound presentation versus a physician's oral presentation. Another trial showed a table with effectiveness categories led to more correct answers than one based on numbers or a table with categories and numbers. One trial examined contraceptive choice: women in the expanded program were more likely to choose sterilization or use a modern contraceptive method. No trial had an explicit theoretical base, but each used concepts from common theories or models. Limited evidence is available concerning what works to help consumers choose an appropriate contraceptive method. Strategies should be examined in clinical settings and assessed for effect on contraceptive choice and retention of knowledge. To expand the knowledge base of what works in contraceptive counseling, randomized trials could intentionally use and test theories or models.