Nominal Group Technique

Nominal Group Technique, or NGT, is a weighted ranking method that enables a group to generate and prioritize a large number of issues within a structure that gives everyone an equal voice.

The tool is called nominal because there is limited interaction between members of the group during the NGT process.

When to use?

When a team needs to create a list of options and rank them, using NGT effectively neutralizes the domination of the loudest person, or the person with the most authority, over the decision-making process.

This tool can also help a team achieve consensus about the relative importance of issues.

The final result may not be everyone’s first priority, but they can live with it.

NGT is a good tool to use when dealing with controversial or emotional issues, or when a group is stuck.

It is particularly useful when you need to :

Reduce the number of issues for easier handling.
Get input from all team members.
Rank items in priority order.

How to use?

NGT is a facilitated process that has two parts. The following description of how to conduct an NGT session :

NGT PART I: The issue is defined and the team generates ideas.

Introduce and clarify the issue to be addressed by the team. Write the issue on a chart pack where everybody can see it. Allow for clarification, but do not let the group engage in a discussion of the issue itself. Remember to define unclear terms.
Generate ideas to address the issue at hand.
Working in silence, each team member writes down his or her ideas on a piece of paper. People should not confer with each other and should sit quietly until everyone finishes writing.
Depending on the complexity of the topic, 5 to 10 minutes should be allowed for the silent process. People need to have enough time to get the broad, general ideas down, but not enough to create long, detailed lists.
Collect the team’s ideas. Each team member, in turn, reads out one of his or her ideas. Write each idea on the chart pack. This round robin should continue until all of the ideas have been offered and recorded. There should be no discussion or side conversations during this part of the session.

NOTE: If post-its are available, you may want to ask the participants to write each of their ideas on a separate sheet and hand them in. You can display the ideas randomly, rather than writing them down. These post-its can be used later to create an Affinity Diagram.

Clarify ideas. Read each idea out loud. If clarification is needed, the person who provided the idea should explain it now. This is an opportunity to clean up the wording of any unclear statements. Others may contribute if necessary.
Combine ideas. Combine like ideas when feasible, but only if both originators agree to it. If they cannot agree, leave the two ideas separate

NGT PART II - The team makes the selection

Assign a letter designation to each separate idea. As with Multi-voting, the facilitator assigns a letter to avoid confusion with the vote tally.
Rank the ideas independently. Each team member writes down the items by their letter designations and assigns them a numeric value based on his or her judgment of what is most important and what is least important.
The highest number is assigned to the most important idea and the lowest to the least important idea. For example, if there are 8 items lettered A to H, the most important receives an 8 and the least important, a 1.
Collate the rankings. The facilitator transcribes the team members’ rankings onto a chart pack, writing each number next to the corresponding idea.
Add the rankings. The facilitator adds the numbers across. The idea with the highest point total is the one of most importance to the whole team. It is the highest priority item.
Rewrite the list. The facilitator rewrites the list of ideas in the order of their importance to the team.
Perform a sanity check. Does the prioritization make sense?

When to use?

How to use?

NGT PART I: The issue is defined and the team generates ideas.

NGT PART II - The team makes the selection

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