What is a Tree Diagram?
Tree diagrams helps link a task's overall goals and sub-goals, and helps make complex tasks more visually manageable. These diagrams encourage team members to expand their thinking when crafting solutions, and allow participants to verify decision-making and assess for completeness at every level of the process. You can use a tree diagram to break down a process into manageable parts, or discover the detailed components of any complex process.
How to Draft a Tree Diagram
1. Draft a Goal Statement
Work to create a clear, action-oriented statement through consensus.
2. Assemble the Right Team
The team should consist of action planners with detailed knowledge of the goal topic. Only take the tree to the level of knowledge the team has, and then prepare to hand the tree off for further detail. 4-6 people are the ideal group size for the Tree Diagram.
3. Generate Tree Headings (Sub-Goals)
- Brainstorm major task areas to create the first level of detail. These are the major "means" by which the goal statement will be achieved.
- Brainstorm action statements, and sort into groupings.
- Choose the header for the grouping; use these header cards as the tree's first-level sub goals.
4. Sketch More Detail
- Working from your goal statement and first-level detail, placed to the right, left or top of the work surface, ask of each first-level item: What needs to be achieved to meet the goal statement? Keep repeating this question for each successive level of detail.
- Stop the breakdown when the detail has reached an assignable task or the team reaches the limit of their expertise. Most trees are broken out at the third level of detail. However, some sub goals are easier to detect and don't require as much breakdown.
- At each level of detail, look for anything you may have forgotten.
- As the tree breaks down into greater detail, ask: If I want to accomplish these results, do I really need to do these tasks?
- As the tree builds to broader goals, ask: Will these actions actually lead to these results?
- Finally, draw the lines connecting the tasks.
Example Tree Diagram
This tree diagram is taken from a PDSA conducted by Brown County Public Health to help establish a partnership coalition focused on improving healthy behaviors of county residents.
Click to view larger.
American Society for Quality
West Central Public Health Initiative Immunization Quality Improvement Project (page 4; PDF)
Kansas Health Institute
The Quality Toolbox
Nancy R. Tague
Public Health Memory Jogger
Public Health Foundation, GOAL/QPC