team members. A short introductory text explicitly guaranteed confidentiality and we explicitly mentioned that only group-level results would be reported back and that individual team members where thus not recognizable. The manager provided data on the performance of each team member as they would normally also do for performance evaluations or end of year talks. On average managers were 41.43 years old (SD=8.47) and had been 59.79 months in their function (SD=70.21), 24 percent of the managers were women. Managers were not included in the analyses because our attention was focused on peer-relationships (see Footnote 1). In our sample, 110 of the 182 respondents were female (60%), the average age was 35.36 years (SD = 9.85), and the average number of years in the organization was 7.42 years (SD = 7.41). Measures Task interdependence. This variable was measured using team members’ responses to three items adapted from past research (Van der Vegt et al., 2003, p. 719; see also Van der Vegt & Van de Vliert, 2005). These items were adapted to be consistent with our other measures and as such we used a 7-point scale (1 = totally disagree, 7 = totally agree) instead of the original scale. An example item is: ‘I have to work closely with my colleagues to do my work properly’. Cronbach’s alpha was .76. An ANOVA revealed that some differences occurred between the groups (F[36,145] = 1.65, p < .05). The subsequently calculated ICC1 demonstrated that only 8 percent of the variance occurred at the team level (ICC1 = .08). These results showed that we needed to include a random intercept in our multi-level analysis to control for possible differences that might occur between teams (e.g., Krull & MacKinnon, 2001). Task autonomy. This variable was measured by the use of respondents’ responses to five 7-point items adapted from Molleman et al. (2004) which we obtained by contacting the main author. The original items were rated on a 5-point scale. An example item is: ‘As a team we are
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