Measures
Anxiety
Each participant in both groups and cohorts at the different time points, completed online via Google Forms the Italian validated version of nine questionnaires:Perceived Stress Scale (PSS)Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS)State Anxiety Inventory (STAIX-1)Mind Wandering Spontaneous (MW-S)Positive and Negative Affect Schedule (PANAS)Difficulties in Emotion Regulation Scale (DERS)Resilience Scale (RS-14)and (ix) Attention Control Shifting and Distraction (AC-S and AC-D)The questionnaires and their psychometric properties are described in detail in the The scores obtained from the questionnaires as measure of the psychological investigated outcomes were used as dependent variables in the statistical models to evaluate the efficacy of our MBI. We also collected at t0 only data from STAI-X2 questionnaires measuring trait anxietyFor the first cohort, we decided to offer the control group the same intervention straight after the measures were acquired at t1, therefore we were unable to collect the follow-up measures (t2). Regarding the second cohort, the treatment group received the intervention before the summer break, and we offered the control group the same intervention after the summer break. This delay allowed us to collect the follow-up measures on participants from the second cohort, who were asked to fill in the same questionnaires at follow-up, after 3 months from the treatment group receiving the last IM class.