Effects of a Smartphone-Based Mindfulness Intervention on Momentary Stress Among First Responders: a Micro-Randomized Trial
Tiffany Tran, Sun-Kyung Lee, Susanne Lee, Amberlee Martin, Abigail H. Gewirtz
Prevention Science August 10, 2026 DOI: 10.1007/s11121-026-01957-5 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Micro-randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 75 |
| Population | First responders |
| Intervention | App-based guided mindfulness practice (MYAPT.MIND) |
| Duration | 30 days |
| Topics | Meditation |
| Key findings | Neither intervention directly reduced momentary stress, but participants assigned to MYAPT.MIND reported smaller increases in momentary stress after a stressor exposure than those receiving a brief message or no intervention, suggesting app-based mindfulness may dampen stress reactivity. |
Abstract
First responders face extreme workplace stressors that can increase symptoms of distress. While mindfulness-based interventions are well-established for stress management, their time-intensive formats may pose barriers for those with long shifts and unpredictable schedules. Smartphone-delivered mindfulness interventions offer a flexible alternative. This study used a micro-randomized controlled trial design to test the effectiveness of two smartphone-delivered mindfulness interventions in reducing momentary stress and stress reactivity to a self-reported stressor. The two interventions included: (1) a text message reminder to engage in a mindfulness practice (brief message) and (2) a prompt to complete an app-based guided mindfulness practice (MYAPT.MIND). Participants were 75 first responders (M = 38.9, SD = 6.8) who completed ecological momentary assessments twice a day (EMA 1 and EMA 2) and received 1 of 3 conditions daily (i.e., no-intervention, brief message, or MYAPT.MIND) between EMA 1 and EMA 2 for 30 days. Multilevel modeling was used to estimate the proximal effects of the daily intervention assignments and to test whether the interventions dampened the impact of stressor exposures on momentary stress at EMA 2. Results indicated no direct effect of interventions on momentary stress. However, participants who were assigned to MYAPT.MIND reported smaller increases in momentary stress following a stressor exposure than for the brief message or control groups. These findings highlight the potential of app-based mindfulness interventions as a "just-in-time" tool for acute stress management.
Comparable studies
Other randomized controlled trials on meditation, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Alterations in Brain and Immune Function Produced by Mindfulness Meditation Healthy employees in a work environment | 2003 | Randomized controlled trial | n = 41 |
| Prevention of relapse/recurrence in major depression by mindfulness-based cognitive therapy. Recovered recurrently depressed patients | 2000 | Randomized controlled trial | n = 145 |
| Open hearts build lives: Positive emotions, induced through loving-kindness meditation, build consequential personal resources. Working adults | 2008 | Randomized controlled trial | n = 139 |
| Short-term meditation training improves attention and self-regulation Undergraduate Chinese students | 2007 | Randomized controlled trial | n = 40 |
| Mindfulness-Based Cognitive Therapy for Depression: Replication and Exploration of Differential Relapse Prevention Effects. Recovered recurrently depressed patients | 2004 | Randomized controlled trial | n = 73 |
Citations in the library
Cites 15
- Mechanisms of mindfulness Journal of Clinical Psychology December 29, 2005
- Mindfulness-Based Interventions in Psychiatry. FOCUS: The Journal of Lifelong Learning in Psychiatry January 24, 2018
- Effectiveness of mindfulness-based interventions on the well-being of healthcare workers: a systematic review and meta-analysis. General Psychiatry 2024
- Mindfulness-Based Mobile Apps and Their Impact on Well-Being in Nonclinical Populations: Systematic Review of Randomized Controlled Trials Journal of Medical Internet Research June 21, 2023
- Effects of mindfulness-based interventions on perceived stress among non-clinical adults: a systematic review and meta-analysis. npj Mental Health Research February 3, 2026
and 10 more in the library