References
device. The comparative SpO2 measurements are illustrated in Figure 14. IJEMT Figure 14: Comparison of HMS and SME SpO2 measurements 3.1.6 Error Analysis The resulting error indices are summarized in Table 3. Heart rate exhibited the highest measurement deviation, with a MAPE of 14.84% and an RMSE of 14.28 bpm. Body temperature recorded the lowest error, with a MAPE of 1.37% and an RMSE of 0.57 °C, while the SpO2 measurements produced a MAPE of 2.66% and an RMSE of 2.85 percentage points. Table 3. Error analysis of the health monitoring system Error Analysis Heart Rate Temperature SpO2 Level MAPE 14.84% 1.37% 2.66% RMSE 14.28 bpm 0.57 °C 2.85 % points 3.2 Discussion At the system level, the successful integration of physiological and environmental sensing, OLED visualization, and local web-based access demonstrates the practical value of the developed platform. The system continuously acquired sensor data and presented measurements simultaneously on the OLED and web interface, confirming the functional integration of sensing, processing, display, and wireless communication. This aligns with previous network-enabled health monitoring systems designed to extend real-time observation beyond conventional clinical settings (Mostafa et al., 2022). The local web interface further reduces dependence on external cloud infrastructure and dedicated mobile applications. For measurement performance, body temperature showed the closest agreement with the reference device, with mean values of 36.49 °C and 36.54 °C for the HMS and SME, respectively, together with a MAPE of 1.37% and an RMSE of 0.57 °C. SpO2 also showed comparatively good agreement, with a MAPE of 2.66% and an RMSE of 2.85 percentage points. However, the consistently higher HMS SpO2 readings suggest a possible positive measurement bias requiring further calibration. These findings are consistent with previous studies showing that wearable and IoT-enabled platforms can support real-time acquisition of physiological parameters (Wan et al., 2018). Heart-rate measurements exhibited greater point-to-point variation despite similar mean values of 88.89 bpm and 88.00 bpm for the HMS and SME, respectively. The MAPE of 14.84% and RMSE of 14.28 bpm indicate lower stability compared with body temperature and SpO2. This is consistent with reports that optical pulse-sensing systems may be influenced by signal quality and implementation conditions (Wu et al., 2020). Further calibration and signal-processing refinement are therefore required. Since the evaluation involved only three subjects under resting conditions, the findings should be IJEMT regarded as preliminary, and broader validation across more participants and activity conditions is required. 4. Conclusion This study developed and evaluated a web-based wearable health monitoring system for real- time measurement of heart rate, blood oxygen saturation (SpO2), body temperature, ambient temperature, and relative humidity. The system integrated physiological and environmental sensing, local OLED visualization, and browser-based wireless access within a compact battery-powered platform. Comparative evaluation against standard medical equipment showed close agreement for body temperature and SpO2, with MAPE values of 1.37% and 2.66% and RMSE values of 0.57 °C and 2.85 percentage points, respectively. Heart-rate measurement showed greater deviation, with a MAPE of 14.84% and an RMSE of 14.28 bpm, indicating the need for improved calibration and signal processing. Overall, the system demonstrates potential as a low-cost platform for continuous personal health monitoring without dependence on cloud infrastructure. Future work should focus on broader validation under diverse participants and activity conditions, improved heart-rate processing, long-term performance assessment, and intelligent analysis of collected health data. 5. Acknowledgement The authors acknowledge the technical assistance provided by the laboratory staff of the Department of Electrical and Electronics Engineering, Olusegun Agagu University of Science and Technology. 6. Declarations Ethics approval and consent to participate Ethical approval for this study was obtained from the Research Ethics Committee of Olusegun Agagu University of Science and Technology (OAUSTECH-REC), with approval number OAUSTECH/2026/001. Participation was voluntary, and informed consent was obtained from all participants. Competing interests The authors declare no competing interests. IJEMT References Aakesh, U., Rajasekaran, Y., & Sudhakar, T. (2023, January). Review on healthcare monitoring and tracking wristband for elderly people using ESP-32. 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