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Effects of Two Educational Posters on Contraceptive Knowledge and Intentions: A Randomized Controlled Trial
Seri Anderson1, Leah Frerichs, Alexander Kaysin
1Departments of Health Policy and Management, Family Medicine, and Maternal and Child Health, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Objective:
To compare the Centers for Disease Control and Prevention's (CDC) contraceptive effectiveness poster with a more patient-centered poster on factors affecting the likelihood of using effective contraceptives.
Methods:
The posters were tested in a randomized controlled trial. Women were eligible if they were aged 18-44 years, could speak and read English, were not pregnant or trying to conceive, and had engaged in vaginal intercourse in the past 3 months. An online survey administered through Amazon Mechanical Turk was used to collect baseline and immediate follow-up data on three primary outcomes: contraceptive knowledge (measured using the Contraceptive Knowledge Assessment), perceived pregnancy risk, and the effectiveness of the contraceptive the woman intended to use in the next year. Subgroup analyses were conducted in women with prior pregnancy scares, low numeracy, and no current contraceptive. Within- and between-group differences were compared for the two randomized groups.
Results:
From January 26 to February 13, 2018, 2,930 people were screened and 990 randomized. For the primary outcomes, the only significant result was that the patient-centered poster produced a greater improvement in contraceptive knowledge than the CDC poster (P<.001). Relative to baseline, both posters significantly improved contraceptive knowledge (CDC +3.6, patient-centered +6.4 percentage points, P<.001) and a constructed score measuring the effectiveness of the contraceptive that women intended to use in the next year (CDC and patient-centered +3 percentage points, P<.01). This is equivalent to 1-17 of every 100 women who viewed a poster changing their intentions in favor of a more effective contraceptive.
Conclusion:
This study suggests that both posters educate women about contraception and may reduce unplanned pregnancy risk by improving contraceptive intentions. Of the three primary outcomes, the patient-centered poster performs significantly better than the CDC poster at increasing contraceptive knowledge.
Clinical Trial Registration:
ClinicalTrials.gov, NCT03372369.
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