The DLI was developed to describe how leadership is shared within schools. Rather than asking only about the principal, it asks staff to rate how far support and supervision are provided by different members of the leadership team, and how well that team works together. In the validation study, leadership functions showed a two-factor structure (support and supervision), while the characteristics of the team formed a single factor, often labelled coherent leadership team.
Teachers are the usual respondents, and the same function items are rated for each leadership position, so the total number of responses depends on how many positions a study includes. Some published versions also add items on participation in decision-making. The Turkish version by Özdemir (2012), tested with 160 teachers in Ankara, has 23 items: 13 on leadership functions and 10 on team coherence. As the inventory appears in a journal article, researchers should contact the authors about use.