Strategies for communicating contraceptive effectiveness
Abstract
Background
Knowledge of contraceptive effectiveness is crucial to making an informed choice. The consumer has to comprehend the pros and cons of the contraceptive methods being considered. Choice may be influenced by understanding the likelihood of pregnancy with each method and factors that influence effectiveness.
Objectives
To review all randomized controlled trials comparing strategies for communicating to consumers the effectiveness of contraceptives in preventing pregnancy.
Search methods
We searched the computerized databases of MEDLINE, POPLINE, CENTRAL, PsycINFO, EMBASE, ClinicalTrials.gov, and ICTRP. We also examined references lists of relevant articles, and wrote to known investigators for information about other published or unpublished trials.
Selection criteria
We included randomized controlled trials that compared methods for communicating contraceptive effectiveness to consumers. The comparison could be usual practice or an alternative to the experimental intervention.
Data collection and analysis
Data were abstracted by two authors and entered into RevMan. For dichotomous variables, the Mantel‐Haenszel odds ratio with 95% confidence intervals (CI) was calculated. For continuous variables, the mean difference was computed.
Main results
Five trials met the inclusion criteria. In one study, knowledge gain favored a slide‐and‐sound presentation versus a physician's oral presentation (mean difference ‐19.00; 95% CI ‐27.52 to ‐10.48). Another trial showed a table with effectiveness categories led to more correct answers than one based on numbers [ORs were 2.42 (95% CI 1.43 to 4.12) and 2.19 (95% CI 1.21 to 3.97)] or a table with categories and numbers [ORs were 2.58 (95% CI 1.5 to 4.42) and 2.03 (95% CI 1.13 to 3.64)]. One trial examined contraceptive choice: women in the expanded program were more likely to choose sterilization (OR 4.26; 95% CI 2.46 to 7.37) or use a modern contraceptive method (OR 2.35; 95% CI 1.82 to 3.03). No trial had an explicit theoretical base, but each used concepts from common theories or models.
Authors' conclusions
We have limited evidence about what works to help consumers choose an appropriate contraceptive method. For presenting pregnancy risk data, one trial showed that categories were better than numbers. In another trial, audiovisual aids worked better than the usual oral presentation. Strategies for communicating information 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.
Plain language summary
Informing consumers about how well birth control works
To make a good choice for birth control, people have to know how well different methods work. The pros and cons of the methods are important. People may choose birth control based on how well the method prevents pregnancy. Consumers also need to know what affects the usefulness of the birth control method.
We did a computer search for randomized trials of ways to inform people about how well birth control methods prevent pregnancy. We wrote to researchers to find other trials. The new program or way to inform people could be compared to the usual practice or to another program or means of informing people.
We found five trials. In one study, women learned more from a slide‐and‐sound format than from having a doctor talk to them. Another trial found that categories were better than numbers in showing how many women might get pregnant with each method. One trial looked at the choice of birth control method. Women in the test program more often chose to be sterilized or to use modern birth control than women with the usual counseling. No trial was clearly based on any learning theory. However, each study used parts of common theories or models.
Little is known about helping consumers choose their method of birth control. Ways to inform people about birth control options should be tested in clinics. Trials should look at the choice of birth control method, along with how much consumers remember later. Trials could use and test theories to learn what works in birth control counseling.
