The instrument used to measure these changes was the Team Development Inventory (TDI) developed by Bronson (1990) and based on the theory of Kormanski and Mozenter (1984 ) after work by Tuckman and Jensen (1977), and
Hersey and Blanchard (1982). The TDI consists of ten items related to team development. It has established face validity and an equivalent forms reliability of .95 (Kormanski & Mozenter, 1984). Individuals responded to each item by circling a number which best represented each member's level of agreement with that item, on a five point modified Likest scale, where 1 was equivalent to strongly disagree and 5 was equivalent to strongly agree.