Sample characteristics are described in Supplementary Material 2 (S2A). The sample was composed of 208 participants with a median age of 43.00 years (IQR= 30.00 – 58.00). To test the stability of the questionnaire over time, we estimated the correlation coefficients between each item response at Time 1 and the same response at Time 2 and between each of the six dimensions investigated in this study in two different times. The results are summarized in S2B in Supplementary Material 2. All correlations were positive and statistically significant, showing that the questionnaire was stable both at the item and at the dimension level.
Before conducting the Factor Analysis, we performed the KMO test and the Bartlett’s test of sphericity to determine if the data was suitable for this type of analysis. The overall MSA was 0.75 and Bartlett's test was statistically significant at 95% confidence level (χ2 = 1281.18). For this reason, we concluded that the data was appropriate.
S2C in Supplementary Material 2 shows the factor loadings related to the EFA conducted at Time 1, which considered the 6 factors described in Kesebir et al. (2019). From the loading, it emerged that the first principal axis (PA1) extracted identified two dimensions (Outlook and Resilience even if one question is missing), while PA2, PA3, PA4, and PA5 each identified a single dimension, respectively Sensitivity to Context, Attention, Social Intuition and Self-Awareness. Finally, PA6 did not identify any dimension. For this reason, this Factor Analysis did not seem to identify the six dimensions correctly. In total, the extracted factors explained 41.6% of the total variance. Next, we determined the internal consistency of each dimension by estimating Cronbach's alphas. The values are summarized in S2D in Supplementary Material 2. Some low values of the Cronbach’s alphas, such as the alpha associated with Social Intuition (α = 0.57), were at the limit of acceptability.
Since the Factor Analysis with six factors did not identify the six dimensions correctly, we conducted the same analysis excluding the items relating to the Outlook and Resilience dimensions with the lowest factor loadings (i.e. items 1, 2, 8, and 14). Therefore, we ran a new EFA by considering only the remaining 20 items.
By performing the KMO test (overall MSA = 0.71) and the Bartlett’s test of sphericity (χ2 = 999.18), we observed that the data was even more suitable for a Factor Analysis. Then, we chose the appropriate number of factors through the parallel analysis. The plot relating to the parallel analysis is shown in Figure 1 and it suggested that the suitable number of factors was five; for this reason, we ran an EFA by extracting only five factors. S2E in Supplementary Material 2 summarizes the factor loadings. As the table shows, each factor extracted identified a single dimension. In fact, the remaining four items related to the Outlook and Resilience dimensions were identified by the first factor and together form the first dimension, which we called “Resilience”; PA3 clearly identified the dimension of “Sensitivity to Context”, PA4 identified the dimension of “Attention”, Social Intuition was identified by PA2 and finally PA5 identified the “Self-Awareness” dimension. In total, the extracted factors explained 41.1% of the total variance.
Regarding the internal consistency, S2F in Supplementary Material 2 shows the Cronbach’s alphas related to the five dimensions. As the table shows, the alphas related to the first dimension increased compared to the previous alphas.
Finally, in the third analysis, we estimated the correlation coefficients between the ESQ total score and the scales and subscales detected in the questionnaire. We used the Spearman’s rank correlation coefficients because by performing the Shapiro-Wilk test we observed that these variables were not normally distributed. The correlation coefficients at TIME 1 are shown in S2G in Supplementary Material 2. As expected, almost all subscales correlated with the score of the appropriate questionnaire.
Study 2
In the light of the results of Study 1, linguistic changes were made to the questionnaire items. In particular, sentences were converted to positive to improve comprehensibility. The final version of the Emotional Style Questionnaire (Italian) is in Supplementary Material 1 (S1). The questionnaires used to investigate psychometric properties were modified in order to observe which constructs each dimension measured. The questionnaires were administered to a group of healthy volunteers stratified by age groups.
Validation protocol
Emotional Style Questionnaire (ESQ)
As in Study 1, participants completed the ESQ and some questionnaires useful to detect the constructs investigated by each dimension.
Depression, Anxiety and Stress Scale (DASS-21)
Description of DASS-21 is provided under Study 1.
Mindful Attention Awareness Scale (MAAS)
Description of MAAS is provided under Study 1.
Multidimensional Assessment of Interoceptive Awareness (MAIA)
MAIA is a multidimensional measure of interoceptive body awareness (Mehling et al., 2012; Committeri et al., 2012). Its 32 items assess eight concepts related to interoceptive awareness (e.g., awareness of body sensations, awareness of the connection between body sensations and emotional states). Participants responded to this measure using a 7-point Likert scale (1 = Strongly Disagree; 7 = Strongly Agree). The MAIA scale was used to test its correlation with the ESQ subscale of self-awareness.
Resilience Scale for Adults (RSA)
Description of RSA is provided under Study 1.
Life Orientation Test - Revised
LOT-R scale, developed by Scheier et al. (Scheier et al., 1994; Giannini et al., 2008), measures people’s expectations regarding the favorability of future outcomes. On a 7-point scale ranging from 1 (Strongly Disagree) to 7 (Strongly Agree), participants indicated their agreement with the statements. The LOT-R scale was used to check its correlation with the Outlook subscale of the ESQ.
Autism Spectrum Quotient (AQ-10)
AQ-10 scale was developed by Allison et al. (Allison et al., 2012; Ruta et al., 2012) and measures the autism level. Participants express their agreement with the sentences on a 7-point Likert scale ranging from 1 (Strongly Disagree) to 7 (Strongly Agree). The AQ-10 scale was used to check its correlation with the social intuition subscale of the ESQ.
Participants
Individuals between the ages of 18 and 75 were included in the study. Participants were recruited by sharing the questionnaire link via mailing lists and social networks. In the questionnaire, in accordance with the criteria provided by the University Bioethics Committee of Università degli Studi di Torino (Italy), there was a description of the project and research objectives and informed consent.
Data analysis
As in Study 1, we have described the data by using the median and interquartile range of frequencies and percentages, while the distribution of the quantitative variables was tested using the Shapiro-Wilk test. Then, we ran an EFA in the new data to identify which items form each of these factors, after checking the suitability of data for a Factor Analysis through the KMO test and the Bartlett’s test of sphericity. The appropriate number of factors was identified through the parallel analysis. Since the data are not normally distributed, we used the PAF as an extraction method of choice. Moreover, we used both varimax and oblimin as rotation methods, which both led to the same conclusions, and then we estimated Cronbach's alpha for each dimension identified. Finally, we estimated the correlation between the total score of each dimension and the scales and subscales detected in the questionnaire, by using the Spearman’s rank correlation coefficient given the non-normality of data. The analyses were conducted both on the entire sample and subjects who reported a DASS depression subscale score ≤ 13 and a DASS anxiety subscale ≤ 9.