Reliability of Smartphone Applications for the Quantification of Oxygen Saturation

Cureus. 2021 Nov 9;13(11):e19417. doi: 10.7759/cureus.19417. eCollection 2021 Nov.

Abstract

Background Smartphone technology is rapidly evolving and advancing, with many of them offering health applications being used for oximetry purposes, including the Samsung Health/S Health application. Measuring oxygen saturation is one of the important indications to monitor patients with COVID-19, as well as other health conditions. These applications can be used for measuring oxygen saturation to provide a convenient solution for clinical decisions. Methods Oxygen saturation measurements were collected using the Samsung Health application for Samsung Galaxy smartphone with a sensor and camera flash and a low-cost portable digital display (liquid crystal display (LCD)) finger pulse oximeter. Intra-session reliability was established to determine the consistency between the measures. Intra-class correlation coefficients (ICCs) were calculated with 95% confidence intervals (CIs) reported for both methods. The Bland-Altman plot was used to compare the level of agreement between the two measurement methods. Results There was a statistically significant average difference between pulse oximeter and Samsung Health application measurements (t125 = 4.407, p < 0.001), and on average, pulse oximeter measurement was 0.510 points higher than Samsung Health application measurement (95% CI = 0.281-0.740). The pulse oximeter and Samsung Health application scores were moderately correlated (r = 0.462). The results of the intra-session reliability test produced an acceptable ICC value of 0.557, indicating moderate reliability and consistent results for the measurement of oxygen saturation with both methods. The Bland-Altman plot showed a consistently equal distribution of data points scattered above and below zero. Conclusion Smartphone health applications can be used with moderate reliability to measure oxygen saturation.

Keywords: bland-altman plot; covid-19; healthcare; oximetry; oxygen saturation; reliability; smartphone health applications; technology.