“…A total of 25 items are rated on a 5-point Likert scale on two different measures – Distress (s-SIB), which is the discomfort participants feel in the situation described in the particular item (not at all, somewhat, rather, very, and extremely) and Performance (s-SIBF), which the is frequency of the described behaviour (I never do, I rarely do, I sometimes do, I usually do, I always do). Example scale items include: for Negative Assertions (NA for distress, FNA for performance) – “Refusing to lend something to a near acquittance,” for Expression and Dealing with Personal Limitations – “Asking someone to show you the way,” for Initiation Assertiveness (IA for distress, FIA for performance) – “Giving your opinion to a person in authority,” and for Positive Assertions (PA for distress, FPA for performance) – “Telling someone that you like him/her.” The s-SIB scales were translated and tested on the Slovak population ( Vráblová and Halamová, 2022 ). The results of the analysis showed good psychometric properties: Cronbach α coefficients for all subscales were – Positive Assertion (distress α = 0.93 and performance α = 0.94), Negative Assertion (distress α = 0.83 and performance α = 0.82), Initiating Assertiveness (distress α = 0.83 and performance α = 0.81), and Expression of and Dealing with Personal Limitations (distress α = 0.79 and performance α = 0.81).…”