Temperament was assessed using the short version of the ATQ translated into Dutch by Hartman and Majdandžić (2001). This questionnaire consists of 77 items and contains the same constructs and sub constructs as the original ATQ (Evans and Rothbart, 2007). Each item is formulated as a statement. Participants in the current study were asked to indicate how applicable this statement was to them by clicking on the appropriate answer option presented on the computer screen. We used a 6-point scale varying from “Not at all” (1) to “Completely” (6). There was also a “not applicable option,” which was treated as missing data point. Supplementary Table 3 shows the number of items and Cronbach’s alpha per (sub)scale.