The effect of adverse information and positive promotion on women's preferences for prescribed contraceptive products

Abstract

Recent rapid growth in the range of contraceptive products has given women more choice, but also adds complexity to the resultant decision of which product to choose. This paper uses a discrete choice experiment (DCE) to investigate the effect of adverse information and positive promotion on women's stated preferences for prescribed contraceptive products. In November 2007, 527 Australian women aged 18-49 years were recruited from an online panel. Each was randomly allocated to one of three information conditions. The control group only received basic information on contraceptive products. One treatment group also received adverse information on the risks of the combined oral pill. The other group received basic information and promotional material on the vaginal ring, newly introduced into Australia and on the transdermal patch, which is unavailable in Australia. Respondents completed 32 choice sets with 3 product options where each option was described by a product label: either combined pill, minipill, injection, implant, hormonal IUD, hormonal vaginal ring, hormonal transdermal patch or copper IUD; and by the attributes: effect on acne, effect on weight, frequency of administration, contraceptive effectiveness, doctor's recommendation, effect on periods and cost. Women's choices were analysed using a generalized multinomial logit model (G-MNL) and model estimates were used to predict product shares for each information condition. The predictions indicated that adverse information did not affect women's preferences for products relative to only receiving basic information. The promotional material increased women's preferences for the transdermal patch. Women in all groups had a low preference for the vaginal ring which was not improved by promotion. The findings highlight the need for researchers to pay attention to setting the context when conducting DCEs as this can significantly affect results.