The effect of an educational intervention based on a mobile application on women’s knowledge, attitudes, and practices with respect to microplastics and health: a randomized controlled trial

BACKGROUND: Microplastic (MP) contamination has emerged as a critical global concern. The most effective approach to mitigating this issue involves substantially minimizing the release of plastic waste into the environment. While addressing such an extensive environmental challenge is inherently complex, public education remains a vital component of any comprehensive solution. In this context, a randomized controlled trial (RCT) was conducted to assess the effectiveness of an educational intervention delivered through a mobile phone application in enhancing women's knowledge, attitudes, and practices concerning the health-related impacts of MPs. METHODS: This two-arm, parallel-design randomized controlled trial (RCT) was conducted from September 2024 to November 2024 with 136 women aged 18 years and older who owned smartphones, had basic literacy skills, and provided informed consent. Participants were recruited through an online call disseminated via social media platforms and health system networks in Iran. They were randomly assigned via block randomization to an intervention group (n = 68) that received the educational program through the app or a control group (n = 68). The sample size was calculated via G*Power software to ensure sufficient power (80%), with an alpha level of 0.05, resulting in a 15% dropout rate. Primary outcome data (Microplastic Knowledge, Attitude, and Practice (MIKAP) questionnaire scores were collected at baseline, immediately postintervention, and 8 weeks postintervention via self-report questionnaires. Data analysis included descriptive statistics and inferential tests, such as independent t tests and paired t tests, to assess group differences and within-group changes over time. RESULTS: Demographic homogeneity was confirmed between the intervention and control groups (P > 0.05 for all baseline variables). The app-based educational intervention significantly improved knowledge scores in the intervention group at posttest 1 (Immediately follow-up; P < 0.001) and posttest 2 (8 weeks later follow-up; P < 0.001), whereas the control group presented declining knowledge (P = 0.009). The attitude scores did not significantly improve in the intervention group (P = 0.155) but significantly decreased in the control group (P = 0.008). Practice scores increased markedly in the intervention group postintervention (P < 0.001), with sustained gains at follow-up, whereas controls showed no significant changes (P = 0.105). Mann‒Whitney tests confirmed significant between-group differences in all outcomes postintervention (P < 0.001). CONCLUSION: The mobile app-based educational intervention effectively enhanced women's knowledge and practices regarding microplastics and health. These findings highlight the potential of digital tools in addressing environmental health challenges through targeted public education. TRIAL STATUS: Protocol Version 1, 2024-07-12. The enrollment of participants began on 2024-09-22. Recruitment is estimated to be completed by 2024-11‒21. TRIAL REGISTRATION: Iranian Clinical Trial Register (IRCT20240529061941N1). URL: https://irct.behdasht.gov.ir/user/trial/77069/view .