RESUMO
OBJECTIVE: To evaluate the effectiveness of a social marketing intervention in enhancing knowledge, attitudes and practice (KAP) related to consumption of vitamin A-fortified oil. DESIGN: The intervention employed community events, distribution of educational materials and radio broadcasts. The intervention was assessed in a quasi-experimental non-equivalent control group study design by collecting information on KAP regarding vitamin A-fortified oil consumption before and after 9 months of a 13-month intervention. SETTING: Six districts in Manyara and Shinyanga regions in Tanzania were non-randomly selected as the intervention districts and two districts served as the control districts. PARTICIPANTS: At baseline, 568 lactating mothers with children aged <5 years were randomly selected from the intervention and control districts. Of these, 494 mothers were followed up at endline. RESULTS: After 9 months of intervention, knowledge of fortification and actual consumption of adequately fortified oil were significantly higher in the intervention districts compared with the control districts (P <0·05). Knowledge of the health benefits of vitamin A improved significantly from about 33 to 45 % in both the intervention and control districts. The major sources of information for women were health clinics and community health workers (CHW). CONCLUSIONS: The study showed that a social marketing intervention is effective in improving KAP regarding fortified oil consumption at the household level. Clinics and CHW are channels that should be prioritized when communicating health messages, particularly those targeting women.