Eritrea faces significant challenges in accessing advanced diagnostic devices due to resource limitations. In vitro diagnostics were designed, tested, and evaluated using a sample of 150 patients with known conditions. The novel diagnostic devices demonstrated an accuracy rate of 92% (CI: 87-96%) in identifying common diseases such as malaria and tuberculosis. The developed diagnostics showed high performance in resource-limited settings, offering a cost-effective alternative to traditional methods. Further clinical trials are recommended to validate these devices across different patient populations. Eritrea, diagnostic devices, biomedical engineering, resource-limited settings The maintenance outcome was modelled as $Y_{it}=\beta_0+\beta_1X_{it}+u_i+\varepsilon_{it}$, with robustness checked using heteroskedasticity-consistent errors.