Statistical analysis
depression
ADVERSE EVENTS
Descriptive statistics were used to present the demographic characteristics of the participants. Numerical data (age, number of outings per week, and outcome measures) were presented as means and standard deviations, whereas categorical data (sex, stress, and favorite aroma) were presented as frequencies and ratio. To determine the improvement in the primary outcome of the scale for stress, changes in DASS-21 scores measured at the time points (weeks 1 and 2) from those measured at the baseline were assessed for each group (aroma- and placebo-seal use group). To determine whether breath comfort while wearing a mask improved, the groups were assessed for improvement in the mask-breathlessness score on week 2. In addition, to assess improvements in mental health by reducing stress caused by wearing a mask, the changes in WHO-5 scores for each group at the time of measurement (week 2) with respect to baseline values were evaluated. To evaluate safety, the number of participants who experienced adverse events and the incidence of these adverse events were recorded for each group. All outcomes were coded using the statistical software SAS (Version 9.4, SAS Institute, Inc., Cary, NC, USA). DASS-21 and mask-breathlessness scores were analyzed using a mixed model for repeated measures (MMRM) with each outcome variable baseline values as covariates. WHO-5 scores were analyzed using a mixed-effects model analysis of covariance, also incorporating each outcome variable baseline values. A p-value < 0.05 for all tests was considered statistically significant. All analyses were conducted using a two-tailed test. To ensure complete data, a Google response form was configured to prevent submissions of incomplete forms, resulting in zero missing values. Except for those who withdrew from the study, all participants completed all outcomes at each time point; therefore, the number of participants for efficacy and safety analyses was the same. Additionally, we calculated Cohen’s d effect sizes for stress, depression, and other relevant measures to assess the practical significance of the results. Efficacy assessments were performed on participants who successfully completed all trial sessions, while safety assessments were conducted for those who received at least one intervention.