The Affinity Diagram as a Brainstorming Tool


Among the many tools available to Six Sigma project teams, the one that consistently is used successfully by all types of teams is the affinity diagram. Also known as the KJ method or a tree diagram, the affinity diagram is a very effective way to manage the brainstorming process and create a more organized approach to the problem at hand.

How does an affinity diagram work?

The affinity diagram works by helping the team organize large numbers of ideas, usually as the result of a brainstorming session. The process allows team members to organize the ideas by category and look at the problem or issues from a new perspective of relationships and patterns.

When team members cooperate to create an affinity diagram, some very important things tend to occur:

· Consensus is reached with less conflict

· Communication is clear and easily understandable

· Every team member contributes

· Ideas are more easily organized into potential solutions

Many Six Sigma practitioners consider the affinity diagram to be one of the most functional tools available because it can be applied to so many different phases of the Six Sigma process.

The steps of affinity diagramming

There are six major steps to creating a good affinity diagram. They are:

· State the problem

· Brainstorm ideas

· Record ideas

· Sort ideas

· Identify common themes or categories

· Create the diagram based on ideas and categories

We’ll look at each of these steps in turn.

State the problem – Unlike the more formal problem statement from the project definition, this statement does not have to be detailed and in fact is easier to work with if it is more simple and straightforward. The problem at hand should be stated in broad terms that capture the essence of the issue or concern.

Brainstorm ideas – With the problem clearly posted nearby, team members start to brainstorm ideas. These should focus on the when, where and how of the problem, not on the why, and the brainstorming does not have to occur aloud.

Record ideas – Some facilitators use sticky notes while others use 3×5 cards, but the only thing that matters is that there is one idea recorded per piece of paper. Each team member records his or her own ideas silently, using clear and concise language, followed by placing each one randomly in the middle of the table or posted on a wall.

Sort ideas – Now ask the team to look over the idea statements and sort them into groups or categories of related ideas. This initial sorting should be done silently, as there will be opportunity for discussion a bit later. The categories themselves should not be identified in advance, but rather emerge naturally through the sorting process. Limit the group to about five categories in all.

Identify common themes or categories – Looking through each grouping of ideas, identify the common theme or subject of each category. Give each category a name, and allow the team time to discussion that name as well as the ideas placed within that category. Team members can clarify statements they wrote if necessary, and express their opinions if they think a particular idea should be in a different category.

Create the diagram – With categories defined, build a diagram with the problem stated at the top and the categories spread below. Place each statement or idea into its assigned category, combining duplicates if necessary. The team can then use the diagram to prioritize the importance of each category and use that information to determine where to turn their process improvement attention.

Getting the most from team members

One of the reasons that affinity diagramming is so effective is that it allows each team member to contribute to their maximum ability. The usual group dynamics do not apply during the brainstorming, so quieter people find it easy to contribute and the range of ideas tends to be much broader.

To get the most from individual team members there should be some basic ground rules established at the beginning of the process:

· During brainstorming, no idea is a bad idea

· All members of the team will contribute to brainstorming

· All ideas will be considered carefully

· The writer of each idea can re-write if necessary to improve clarity

· All members of the team will contribute to discussion

· During discussion, all members are treated with respect

It is the responsibility of the facilitator to discuss the ground rules and enforce them throughout the process. The discussion phase is typically the most contentious part of affinity diagramming, so particular care should be taken to ensure a healthy environment is maintained for all team members.

Affinity Diagram Step


State The Problem

· Simple

· Straightforward

· Broad terms

Brainstorm Ideas

· Focus on the when, where and how

· Does not have to occur aloud

· All ideas are welcome

· All members participate

Record Ideas

· Sticky notes, 3×5 cards, etc.

· One idea per paper

· Recording done silently

· Clear, concise wording of ideas

· Papers placed randomly in designated spot

Sort Ideas

· Conducted silently

· Team members sort ideas into common categories or themes

· Categories not defined in advance

· Limit to about five categories

Identify Categories/Themes

· Identify common them or subject of each grouping

· Name the category

· Group discussion of categories

· Group discussion of placement of ideas within categories

· Team members can rewrite or revise their written statements as needed

Create Diagram

· Stated problem at the top

· Categories spread below

· Place each idea in proper category, combining duplicates if necessary

· Team prioritizes the importance of each category

· Use diagram to determine where to focus process improvement attention next


Source by Peter Peterka