$$\rightleftharpoonup{xx}$$
$$\longleftharp{xx}$$,
$$\longrightharp{xx}$$,
This study was reviewed and approved by the Institutional Review Board of Shijiazhuang Institute of Railway Technology. All procedures complied with the Declaration of Helsinki and relevant local regulations. The equipment and software used are listed in the Table of Materials.
1. Methodology
This study used a quasi-experimental design to evaluate an AI-guided atomization sensing system for digital health education in higher-education settings. Data were collected before and after the intervention to assess knowledge retention, engagement, behavioral intention, self-efficacy, and technology acceptance using validated instruments adapted from prior work. The overall workflow of sensing, AI decision-making, and adaptive instructional delivery is illustrated in Figure 1, which outlines how physiological and environmental signals are integrated into the rule-based and machine-learning components to adjust content in real-time.
2. Statistical analyses
Data analysis was performed using SPSS version 25, with significance set at p < 0.05. Four statistical approaches were applied:
- ANOVA was used to compare between-group differences across the five outcome variables, calculated using the formula:

where MS represents the mean square values derived from sums of squares divided by their degrees of freedom.
- Paired-sample t-tests assessed within-group improvements from pre- to post-test using:

where d is the mean difference, s_d the standard deviation of differences, and n the sample size.
- Chi-square tests were applied to examine associations between categorical outcomes and group allocation:
![figure-protocol-3 Chi-squared formula: χ² = Σ[(O-E)²/E], equation for statistical analysis, hypothesis testing.](/files/ftp_upload/69071/69071eq3.jpg)
where O is the observed frequency and E the expected frequency.
- Pearson correlation coefficients were computed to determine the strength and direction of associations among continuous variables:

with values ranging from -1 to 1, where coefficients above 0.5 were interpreted as moderate to strong positive correlations.
3. Participants
A total of 356 participants aged 18-45 years (M = 26.7, SD = 5.4) were recruited from higher education institutions, met the inclusion criteria for age and basic technological literacy, and provided informed consent. Participants were assigned by random-number table to an intervention group (n = 178) receiving adaptive, AI-guided instruction or a control group (n = 178) receiving conventional modules without personalization. Table 1 summarizes baseline characteristics; the distribution of demographic characteristics across participant subgroups is visualized in Figure 2, which complements the tabulated statistics and confirms group comparability at baseline.
4. Apparatus and materials
The platform integrated wearable sensing of respiratory patterns, ambient temperature, and motion with an AI engine combining rule-based logic and SVM classification to trigger adaptive delivery upon signs of fatigue or reduced activity. Sessions were conducted in standardized multimedia classrooms (~50 m2) equipped with projectors and sensor base stations, lasted 45 min, and were delivered twice weekly over six weeks.
5. Measurement instruments
All self-report instruments were administered on a 5-point Likert scale (1 = strongly disagree to 5 = strongly agree), with higher scores indicating stronger endorsement of the target construct. Items were positively keyed unless otherwise specified, and scale scores were computed as the mean of their constituent items.
6. Knowledge retention
A 15-item multiple-choice test aligned with the instructional content was used to assess knowledge (total score range 0-15). Higher scores reflected greater knowledge acquisition. An example item was: "What is the primary energy source during aerobic exercise?"
7. Behavioral intention
Behavioral intention was measured with a 3-item instrument adapted from the Theory of Planned Behavior20. A representative item was: "I intend to adopt the health practices introduced in class during the following week."
8. Engagement
Engagement was evaluated with a 5-item instrument adapted from a validated framework of learning engagement capturing attention, interaction, emotional involvement, persistence, and learning satisfaction21. An illustrative statement was: "I was able to stay focused during the learning process."
9. Self-efficacy
Self-efficacy was assessed with a 4-item instrument grounded in the established conceptualization of perceived capability. A sample item was: "I am confident that I can independently complete the health exercises demonstrated in class."
10. Technology acceptance
Technology acceptance was measured with a 6-item adaptation of the Unified Theory of Acceptance and Use of Technology, covering performance expectancy, effort expectancy, social influence, and facilitating conditions. A representative item was: "Using this system can enhance my learning performance."
All instruments demonstrated acceptable to strong internal consistency in the present study: α = 0.87 (Knowledge), 0.82 (Behavioral Intention), 0.85 (Engagement), 0.84 (Self-efficacy), and 0.89 (Technology Acceptance).