The intervention is delivered via the internet and is grounded in the psychopathological diamond model of emotional distress proposed by Liu and colleagues. The program is supported by a MIED knowledge base, the Mindfulness Study public account, supervision and question-answer records, and official materials from Liu Xinghua and the MIED team. These resources are integrated into a WeChat self-help mini-program and the MIED Mindfulness Assistant, an artificial intelligence-supported system developed using large language models such as Tencent Hunyuan and DeepSeek R1. Together, these tools support participants' learning and practice over a continuous 49-day training period.

The ODSIS is a 5-item self-report measure designed to assess the frequency and severity of depressive symptoms, as well as depression-related functional impairment and avoidance, over the past week. Each item is rated on a 5-point scale from 0 to 4, with total scores ranging from 0 to 20. Higher scores indicate greater overall depression severity and impairment. The ODSIS has demonstrated good reliability and validity in both clinical and nonclinical samples (Bentley et al., 2014).

The GERD-Q is a 6-item self-report questionnaire used to assess the frequency and severity of gastroesophageal reflux symptoms and to monitor treatment response. Total scores range from 0 to 18, with higher scores indicating more severe reflux-related symptoms.

The RSI is a 9-item self-report questionnaire used to assess symptoms related to laryngopharyngeal reflux, including chronic cough, hoarseness, throat clearing, and globus sensation. Total scores range from 0 to 45, with higher scores indicating more severe reflux-related throat symptoms.

The GAD-7 is a 7-item self-report questionnaire used to assess the severity of anxiety symptoms over the past 2 weeks. Each item is rated on a 4-point scale from 0 ("not at all") to 3 ("nearly every day"), with total scores ranging from 0 to 21. Higher scores indicate greater anxiety severity. The GAD-7 has demonstrated good reliability and validity in both clinical and general populations (Spitzer et al., 2006).

The PHQ-9 is a 9-item self-report questionnaire used to assess the severity of depressive symptoms over the past 2 weeks. Each item is rated on a 4-point scale from 0 ("not at all") to 3 ("nearly every day"), with total scores ranging from 0 to 27. Higher scores indicate greater depression severity. The PHQ-9 has demonstrated good reliability and validity in both clinical and general populations (Kroenke et al., 2001).

TIC-P is a widely used health economic instrument in mental health research for assessing psychiatric healthcare use and societal costs, including service utilization, medication use, and productivity losses (Bouwmans et al., 2013). In this study, TIC-P will be used to record healthcare resource consumption during the trial, including outpatient visits, medication costs, and other healthcare-related expenditures. To capture healthcare utilization more comprehensively, a self-developed healthcare utilization questionnaire will also be administered.

This is one of the most widely used instruments in health economic evaluation for measuring health-related quality of life and includes five dimensions: mobility, self-care, usual activities, pain/discomfort, and anxiety/depression, each with five response levels (Devlin & Brooks, 2017; Herdman et al., 2011). The health utility values derived from EQ-5D-5L will be used to calculate Quality-Adjusted Life Years (QALYs) for cost-utility analysis (Drummond et al., 2015; Group, 1990).

The ISI is a 7-item self-report questionnaire used to assess the severity of insomnia symptoms and the degree of sleep-related impairment. Total scores range from 0 to 28, with higher scores indicating greater insomnia severity.

The CD-RISC is a self-report questionnaire used to assess psychological resilience and the ability to cope with stress and adversity. Higher scores indicate greater resilience.

The Chinese Perceived Stress Scale (CPSS) will be used to assess participants' subjective perception of life stress. This scale is derived from the Perceived Stress Scale developed by Cohen et al., and primarily assesses the extent to which individuals perceive life events over the past month as unpredictable, uncontrollable, and overwhelming (Cohen et al., 1983). The Chinese version of the CPSS has been applied and validated in Chinese populations, with studies demonstrating good internal consistency, structural validity, and criterion-related validity, supporting its use for assessing subjective stress levels (Leung et al., 2010; Ng, 2013).

The SWLS is a self-report questionnaire used to assess global cognitive judgments of life satisfaction. Higher scores indicate greater life satisfaction.

To evaluate the safety of the intervention, this study will record adverse events (AEs) and serious adverse events (SAEs) occurring during the study period. These events will be defined, documented, and reported in accordance with international clinical trial guidelines, and will be descriptively analyzed with respect to the time of occurrence, severity, relationship to the intervention, and outcome

The Engaging in Life Scale will be used to assess the degree to which individuals engage in key life domains such as work, study, social interaction, and sleep, and is an important tool for evaluating levels of engagement in life (Chen et al., 2026).

Distress tolerance will be assessed using the Distress Tolerance Scale (DTS), which measures individuals' capacity to tolerate negative emotional experiences and their regulatory responses to emotional distress (Simons & Gaher, 2005).

The Discomfort Intolerance Scale (DIS) will be used to assess tolerance of unpleasant bodily sensations, which has been widely applied in anxiety disorder and emotion regulation research (Schmidt et al., 2006).

The Excessive Emotional Behavior Scale (EEBS) will be used to assess excessive emotion-driven and avoidant behaviors under negative affective states, thereby providing a more comprehensive assessment of this psychological process (Zhang et al., 2026).

The Brief Experiential Avoidance Questionnaire (BEAQ) will be used to further assess experiential avoidance as a core process (Gámez et al., 2014).

Cognitive flexibility will be measured using the Cognitive Flexibility Inventory (CFI), which assesses individuals' ability to shift cognitive frameworks, generate alternative explanations, and adopt adaptive thinking strategies under stress (Dennis & Vander Wal, 2010).