The problem we focused on
Advances in the arms industry and changes in warfare strategies over the last decades have shifted the battlefield into the civilian backyard, greatly increasing citizen vulnerability . Exposure to war can have catastrophic and long-lasting effects not only on one’s physical health, but also on one’s mental health and psychosocial well-being . But how does war affect individuals in real-time? Our study  sheds light on this issue by tracking with modern technology the real-time impact of the May 2021 Israel-Gaza armed conflict on Israelis’ well-being.
How did it all start?
The current study is part of a larger study called PerMed . The goal of PerMed is to provide earlier and improved diagnosis of highly common acute infectious diseases through the combined use of Electronic Medical Records (EMRs), behavioral information collected from smartphones and smartwatches, and daily questionnaires. The May 2021 Israel-Gaza armed conflict occurred during the PerMed study, providing us with a unique opportunity to examine how war impacts individuals.
What did we do?
We equipped 954 participants (>40 years; 57.55% women) with smartwatches and a mobile application with daily questionnaires on well-being, which allowed us to track their physiological state and receive their self-reported evaluation of their well-being for the period starting two weeks before the war and ending four weeks after the ceasefire.
The daily questionnaire consisted of questions about the mental and physical health of the participants: mood level, stress level, sleep duration, sleep quality, sport time, and number of social encounters (Figure 1). The mobile app also collected data about the participant’s phone’s screen-on time and the percentage of time still (according to Google Activity Recognition).
The Garmin smartwatch collected daily aggregated indicators about step count, average heart rate and sleep data.
What did we find?
We found that the sirens raised to warn citizens of possible incoming missiles and prompt them to take shelter, led to a considerable increase in the heart rate of the participants (Figure 2).
We also found that during missile attacks and throughout the war, individuals experienced considerable changes in all the examined well-being indicators: screen-on time, step count, average heart rate, percentage of time still, awake time during night sleep, and sleep start hour, as well as the self-reported mood level, stress level, number of encounters, sport time, sleep duration, and sleep quality.
Interestingly, after the war, all these measures returned to baseline levels in nearly all the participants. An example for three of the 12 examined well-being indicators is provided in Figure 3.
We also observed that individuals living closer to the battlefield, women, and younger individuals experienced greater changes in their well-being indicators during the war.
Conclusions and implications of our study
Our study offers valuable insights into how wars impact individuals' wellbeing in real-time. By using modern technology to monitor wellbeing, we were able to identify changes that may have gone unnoticed in retrospective studies.
Indeed, our study highlights the significant physiological changes that people undergo during wartime, as well as the variation across different populations. This proof-of-feasibility for the automatic identification of people in need of support in real-time opens the way for the development of systems for issuing immediate assistance for individuals in distress.
Furthermore, the study illustrates the resilience of the Israeli society, which returned to normal immediately following an intense week, during which over 4,300 rockets and missiles were launched toward Israeli cities.
Moving forward, future research could build on our findings by exploring how different types of crises, such as natural disasters or pandemics, affect people's well-being in real-time. Additionally, researchers could test potential interventions designed to mitigate the negative effects of crises on individuals' wellbeing. Our hope is that our findings will inform future research and inspire others to use technology to improve the lives of people affected by crises.
 Khorram-Manesh, A., Burkle, F. M., Goniewicz, K. & Robinson, Y. Estimating the Number of Civilian Casualties in Modern Armed Conflicts–A Systematic Review. Front. Public Heal. 9, 1614 (2021).
 Norris, F. H., Friedman, M. J. & Watson, P. J. 60,000 Disaster Victims Speak: Part II. Summary and Implications of the Disaster Mental Health Research. https://doi.org/10.1521/psyc.220.127.116.1169 65, 240–260 (2005).
 Mofaz, M. et al. Real-time sensing of war’s effects on wellbeing with smartphones and smartwatches. Commun. Med. 2023 31 3, 1–11 (2023).
 Tel Aviv University. The permed study.https://www.permed.sites.tau.ac.il/(2022)