What this trial measures

• Applied MindfulnessBaseline and intervention completion (~10 weeks)

  Students will complete the Applied Mindfulness Process Scale (AMPS) at baseline and post-intervention completion. The scale consists of 15 questions that quantify the application of mindfulness skills to navigate difficult situations and stressors in life. The AMPS encompasses three subscales: decentering, negative emotion regulation, and positive emotion regulation. The total scores are the sum of the item scores. The total possible scores range from 0 to 60. Higher scores reflect a more active use of mindfulness practice in everyday life. The scale demonstrated high internal consistency (Cronbach's α = 0.91) among 134 adults in the original study.

• Trait MindfulnessBaseline and intervention completion (~10 weeks)

  Trait mindfulness will be assessed with the Five Facet Mindfulness Questionnaire (FFMQ), a 39-item questionnaire evaluating five distinct components of mindfulness: observation (8 items), description (8 items), aware actions (8 items), non-judging of inner experience (8 items), and non-reactivity to inner experience (7 items). The total score is the average across the five subscales. Possible scores range from 1 to 5, with higher scores indicating higher dispositional mindfulness.

• Physiological Stress Response to an Acute StressorIntervention completion (~8 and 9 weeks)

  At the time of intervention completion, physiological stress reactivity will be evaluated using the online version of the Trier Social Stress Test (TSST) in our laboratory (Heyers et al., 2025). During the TSST, heart rate will be measured using a chest-worn Polar H10 (Polar Electro Oy, Kempele, Finland) (Schaffarczyk et al., 2022) and video-based photoplethysmography (PPG) (Pirzada et al., 2023). Wrist collected PPG heart rate data will also be measured during the TSST-OL (ActiGraph LEAP; Ametris, Pensacola, Florida). Raw inter-beat intervals will be recorded via Bluetooth pairing with an accelerometer (ActiGraph wGT3X-BT; Ametris, Pensacola, Florida). The mean heart rate (MHR) will be computed during the baseline resting phase, the TSST (speech preparation and speaking), and the recovery phase (Nyklíček et al., 2013). Reactivity to the acute stressor will be operationalized as differences in heart rate parameters during the TSST (preparation + speaking) compared to the baseline.

• Well-BeingBaseline and intervention completion (~10 weeks)

  Well-being will be assessed with the 5-item World Health Organization Well-Being Index (WHO-5). Participants will rate five positively phrased items on subjective well-being, i.e., "I have felt cheerful and in good spirits." Responses are anchored from 0 (none of the time) to 5 (all the time). The total score is the sum of item responses ranging from 0 to 25, with 25 indicating the maximum possible mental well-being. The index has shown high internal consistency with α = 0.86 and test-retest reliability of r = 0.77 in 903 college students.