Background The detection of early changes in vital signs (VSs) enables timely intervention; however, the measurement of VSs requires hands-on technical expertise and is often time-consuming. The contactless measurement of VSs is beneficial to prevent infection, such as during the COVID-19 pandemic. Lifelight is a novel software being developed to measure VSs by remote photoplethysmography based on video captures of the face via the integral camera on mobile phones and tablets. We report two early studies in the development of Lifelight. Objective The objective of the Vital Sign Comparison Between Lifelight and Standard of Care: Development (VISION-D) study (NCT04763746) was to measure respiratory rate (RR), pulse rate (PR), and blood pressure (BP) simultaneously by using the current standard of care manual methods and the Lifelight software to iteratively refine the software algorithms. The objective of the Vital Sign Comparison Between Lifelight and Standard of Care: Validation (VISION-V) study (NCT03998098) was to validate the use of Lifelight software to accurately measure VSs. Methods BP, PR, and RR were measured simultaneously using Lifelight, a sphygmomanometer (BP and PR), and the manual counting of RR. Accuracy performance targets for each VS were defined from a systematic literature review of the performance of state-of-the-art VSs technologies. Results The VISION-D data set (17,233 measurements from 8585 participants) met the accuracy targets for RR (mean error 0.3, SD 3.6 vs target mean error 2.3, SD 5.0; n=7462), PR (mean error 0.3, SD 4.0 vs mean error 2.2, SD 9.2; n=10,214), and diastolic BP (mean error −0.4, SD 8.5 vs mean error 5.5, SD 8.9; n=8951); for systolic BP, the mean error target was met but not the SD (mean error 3.5, SD 16.8 vs mean error 6.7, SD 15.3; n=9233). Fitzpatrick skin type did not affect accuracy. The VISION-V data set (679 measurements from 127 participants) met all the standards: mean error −0.1, SD 3.4 for RR; mean error 1.4, SD 3.8 for PR; mean error 2.8, SD 14.5 for systolic BP; and mean error −0.3, SD 7.0 for diastolic BP. Conclusions At this early stage in development, Lifelight demonstrates sufficient accuracy in the measurement of VSs to support certification for a Level 1 Conformité Européenne mark. As the use of Lifelight does not require specific training or equipment, the software is potentially useful for the contactless measurement of VSs by nonclinical staff in residential and home care settings. Work is continuing to enhance data collection and processing to achieve the robustness and accuracy required for routine clinical use. International Registered Report Identifier (IRRID) RR2-10.2196/14326

BACKGROUND Detection of early changes in vital signs (VS) enables timely intervention; however, measurement of VS requires hands-on technical expertise and is often time-consuming. Contactless measurement of VS is beneficial to prevent infection, such as during the COVID-19 pandemic. Lifelight® is a novel software being developed to measure VS by remote photoplethysmography, based on video capture of the face via the integral camera on mobile phones and tablets. We report the observational VISION-D data collection study for algorithm development (NCT04763746) and VISION-V (NCT03998098), a laboratory-based validation study of Lifelight. OBJECTIVE Data collection for algorithm development (VISION D) and software validation (VISION V) METHODS Blood pressure (BP), pulse rate (PR), and respiratory rate (RR) were measured simultaneously using Lifelight, a sphygmomanometer (BP, PR) and manual counting of RR. Accuracy performance targets for each VS were defined from a systematic literature review of the performance of state-of-the-art VS technologies. RESULTS The VISION-D dataset (17,233 measurements from 8585 participants) met the accuracy targets for RR (0.3 ± 3.6 [mean error ± SD] vs target of 2.3 ± 5.0; n=7462), PR (0.3 ± 4.0 vs 2.2 ± 9.2; n=10,214), and diastolic BP (−0.4 ± 8.5 vs 5.5 ± 8.9; n=8951); for systolic BP, mean error target was met but not SD (3.5 ± 16.8 vs 6.7 ± 15.3; n=9233). Fitzpatrick skin type did not affect accuracy. The VISION-V dataset (679 measurements from 127 participants) met all the standards: −0.1 ± 3.4 for RR; 1.4 ± 3.8 for PR; 2.8 ± 14.5 for systolic BP; −0.3 ± 7.0 for diastolic BP. CONCLUSIONS Lifelight demonstrates sufficient accuracy in the measurement of VS, particularly RR and PR, which are important early indicators of clinical deterioration. As use of Lifelight does not require specific training or equipment, the software is potentially useful for the contactless measurement of VS by non-clinical staff in residential and home care settings. INTERNATIONAL REGISTERED REPORT RR2-10.2196/14326