Recommending Tolerance Value for SpO2 Devices with Linear Regression Based on Measuring Tape

Monitoring blood oxygen levels is vital for tracking various respiratory diseases like bronchitis, pneumonia, COPD, and critical care patients, including those with COVID-19. SpO2 devices, calculating oxygen percentage via finger or earlobe tissue, play a crucial role. Field studies have revealed concerns regarding the accuracy of SpO2 measurements due to high deviations, particularly in patients with low oxygen saturation, prompting the initiation of this study to ensure accurate interpretation of the device's measurements. Using a linear regression algorithm, SpO2 values from different bands were classified for quality. Tolerance values and deviation thresholds for each band were recommended. Additionally, linear regression aimed to save time by making result estimations with less data, facilitating more device monitoring and frequent testing. Results closely matched actual values, suggesting contributions to more frequent application and rapid interpretation. Following the European standard 80601-2-61, measurements were taken from three pulse oximeter brands (Contec MS100 model simulator) in three bands: 70-79%, 80-89%, and 90-100% SpO2. For each measurement, an Arms curve graph was generated using linear regression, and the mean square error (MSE) and Arms values were calculated to evaluate devices. In conclusion, deviation rates increase at low oxygen saturation levels, and recommended % SpO2 deviation values were proposed for each band and device quality.