Health Care Workers’ Need for Headspace: Findings From a Multisite Definitive Randomized Controlled Trial of an Unguided Digital Mindfulness-Based Self-help App to Reduce Healthcare Worker Stress

BACKGROUND: Health care workers experience high stress. Accessible, affordable, and effective approaches to reducing stress are lacking. In-person mindfulness-based interventions can reduce health care worker stress but are not widely available or accessible to busy health care workers. Unguided, digital, mindfulness-based self-help (MBSH) interventions show promise and can be flexibly engaged with. However, their effectiveness in reducing health care worker stress has not yet been explored in a definitive trial. OBJECTIVE: This study aimed to investigate the effectiveness of an unguided digital MBSH app (Headspace) in reducing health care worker stress. METHODS: This was a definitive superiority randomized controlled trial with 2182 National Health Service staff in England recruited on the web and allocated in a 1:1 ratio to fully automated Headspace (n=1095, 50.18%) or active control (Moodzone; n=1087, 49.82%) for 4.5 months. Outcomes were subscales of the Depression, Anxiety, and Stress (primary outcome) Scale short form; Short Warwick Edinburgh Mental Well-being Scale; Maslach Burnout Inventory; 15-item Five-Facet Mindfulness Questionnaire minus Observe items; Self-Compassion Scale–Short Form; Compassionate Love Scale; Penn State Worry Questionnaire; Brooding subscale of the Ruminative Response Scale; and sickness absence. RESULTS: Intention-to-treat analyses found that Headspace led to greater reductions in stress over time than Moodzone (b=–0.31, 95% CI –0.47 to –0.14; P<.001), with small effects. Small effects of Headspace versus Moodzone were found for depression (b=–0.24, 95% CI –0.40 to –0.08; P=.003), anxiety (b=–0.19, 95% CI –0.32 to –0.06; P=.004), well-being (b=0.14, 95% CI 0.05-0.23; P=.002), mindfulness (b=0.22, 95% CI 0.09-0.34; P=.001), self-compassion (b=0.48, 95% CI 0.33-0.64; P<.001), compassion for others (b=0.02, 95% CI 0.00-0.04; P=.04), and worry (b=–0.30, 95% CI –0.51 to –0.09; P=.005) but not for burnout (b=–0.19, –0.04, and 0.13, all 95% CIs >0; P=.65, .67, and .35), ruminative brooding (b=–0.06, 95% CI –0.12 to 0.00; P=.06), or sickness absence (γ=0.09, 95% CI –0.18 to 0.34). Per-protocol effects of Headspace (454/1095, 41.46%) versus Moodzone (283/1087, 26.03%) over time were found for stress, self-compassion, and compassion for others but not for the other outcomes. Engagement (practice days per week) and improvements in self-compassion during the initial 1.5-month intervention period mediated pre- to postintervention improvements in stress. Improvements in mindfulness, rumination, and worry did not mediate pre- to postintervention improvements in stress. No serious adverse events were reported. CONCLUSIONS: An unguided digital MBSH intervention (Headspace) can reduce health care workers’ stress. Effect sizes were small but could have population-level benefits. Unguided digital MBSH interventions can be part of the solution to reducing health care worker stress alongside potentially costlier but potentially more effective in-person mindfulness-based interventions, nonmindfulness courses, and organizational-level interventions. TRIAL REGISTRATION: International Standard Randomised Controlled Trial Number ISRCTN15424185; https://tinyurl.com/rv9en5kc