Accuracy of Smartphone-based Vital Monitoring Using Remote Photoplethysmography Technology Enabled WellFie application

Background Remote health monitoring technologies gained interest in the context of COVID-19 pandemic with potential for contactless monitoring of clinical patient status. Here, we examined whether vital parameters can be determined in a contactless manner using a novel smartphone-based technology called remote photoplethysmography (rPPG) and compared with comparable certified medical devices. Methods We enrolled a total of 150 normotensive adults in this comparative cross-sectional validation study. We used an advanced machine learning algorithm in the WellFie application to create computational models that predict reference systolic, diastolic blood pressure (BP), heart rate (HR), and respiratory rate (RR) from facial blood flow data. This study compared the predictive accuracy of smartphone-based, rPPG-enabled WellFie application with comparable certified medical devices. Results When compared with reference standards, on average our models predicted systolic blood pressure (BP) with an accuracy of 93.94%, diastolic BP with an accuracy of 92.95%, HR with an accuracy of 97.34%, RR with accuracy of 84.44%. For the WellFie application, the relative mean absolute percentage error (RMAPE) for HR was 2.66%, for RR was 15.66%, for systolic BP was 6.06%, and for diastolic BP was 7.05%. Conclusion Our results on normotensive adults demonstrates that rPPG technology-enabled Wellfie application can determine BP, HR, RR in normotensive participants with an accuracy that is comparable to clinical standards. WellFie smartphone application based on rPPG technology offers a convenient contactless video-based remote solution that could be used in any modern smartphone. ### Competing Interest Statement The authors have declared no competing interest. ### Funding Statement This study did not receive any funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee/IRB of Ayurvedic and Unani Tibbia College and Hospital gave ethical approval for this work I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines and uploaded the relevant EQUATOR Network research reporting checklist(s) and other pertinent material as supplementary files, if applicable. Yes All data produced in the present study are available upon reasonable request to the authors.