Mobile Phone-Based Education Transforms HIV Self-Testing Knowledge and Uptake Among Female Sex Workers in Nigeria: A Quasi-Experimental Study

Rationale: Female sex workers (FSWs) are a key population at high risk of HIV infection, yet uptake of HIV testing remains low due to stigma, limited access, and knowledge gaps. Mobile phone-based education (MPBE) offers a potential strategy to improve awareness and self-testing behaviors in this population. Objectives: This study evaluated the effect of MPBE on HIV and HIV self-testing (HIVST) knowledge, and on HIVST uptake among FSWs in Bayelsa State, Nigeria. Methods: A quasi-experimental design was employed, with 282 FSWs enrolled into intervention (n = 137) and control (n = 145) groups. Baseline and endline assessments measured socio-demographic characteristics, HIV knowledge, HIVST knowledge, and HIVST uptake. The intervention involved structured mobile-based educational messaging over five weeks. Data were analyzed using chi-square, Fisher’s exact test, independent t-tests, and difference-in-difference (DID) analysis, with statistical significance set at P < 0.05. Results: Baseline socio-demographics were largely comparable, although educational level and marital status differed between groups. HIV knowledge improved markedly in the intervention group, with good knowledge increasing from 57.0% to 99.3% (DID = 38.7 percentage points, 95% CI: 0.25–0.53, P < 0.001), compared with minimal change in the control group (61.2% to 64.8%, P = 0.296). HIVST knowledge increased from 1.2% to 97.1% (DID = 84.9 percentage points, 95% CI: 0.79–0.91, P < 0.001). HIVST uptake rose from 2.4% to 74.5% in the intervention group versus 1.2% to 22.1% in the control group (DID = 51.2 percentage points, 95% CI: 0.41–0.61, P < 0.001). Conclusion: MPBE significantly improved HIV and HIVST knowledge and substantially increased HIVST uptake among FSWs. Recommendations: Integrating mobile-based education into HIV prevention programs can enhance early testing, linkage to care, and reach high-risk populations. Long-term strategies should ensure equitable access to mobile technology and evaluate sustainability. Thus, this intervention offers a scalable approach to empower FSWs, reduce undiagnosed HIV infections, and strengthen HIV prevention efforts in resource-limited settings.