Nominal Group Technique Definition, Examples Steps

In this post, we will talk about Nominal Group Technique, commonly referred to as NGT. Nominal Group Technique is a structured method of brainstorming, where the participants come with ideas on their own rather than as a group. And then, the group collectively evaluates, ranks them according to their importance and agree upon these generated ideas. We will look at what Nominal Group Technique is, when and how to perform nominal group technique, its advantages and disadvantages as well as a few examples where this technique can be used.

Nominal Group Technique – An alternative to traditional brainstorming

Imagine the traditional way of brainstorming. You put a few people in a room and put a problem in front of them to discuss and solve. All the participants start throwing their ideas on the table. Some more vocally than others. You will notice some people in such a group who do not participate, or maybe participate less than others.

You will also find on multiple occasions, that the group gets hanged-up on a particular idea. And keeps discussing the same for the whole duration of the session. This prevents further idea generation and halts the process, you always have limited time for such discussions. Furthermore, it also happens that, at the end of such sessions, the final output is not concrete or tangible enough as you would have expected.

This is because, traditional group brainstorming exercise lacks a structure or defined process. It is a free flowing discussion. The facilitator might sometimes be able to solve for such problems but not always.

Nominal Group Technique solves for such shortcomings of traditional brainstorming exercise and provide you with better results.

So, what exactly is NGT? Let’s see.

What is Nominal Group Technique?

Simple, think of it as structured brainstorming.

Nominal Group Technique is a highly structured, face to face group discussion method where every participant is provided an opportunity to participate. Where opinions of all participants are considered equally important and are heard by other members.

It takes the brainstorming process a notch ahead by adding a voting process. And not just a simple voting process but a relative ranking process. This is in addition to the discussions off-course. This allows the participants to be more engaged in the discussion, and thereby, in solution design.

Nominal means ‘in name only’. Thus, although this is a group technique, it is so, only in name. It is more of individual exercise than a group activity. It is an individual activity which is done as part of a group. Hence the name, Nominal Group Technique.

Delbecq and Van de Ven are the two people who designed and conceptualised Nominal Group Technique. Their original design has 4 key steps which we will discuss below.

Nominal Group Technique Steps

The four steps provide the structure to this technique. You should follow these steps once you have decided on the problem that you wish to solve for. And when you have finalised the list of people or participants who will take part in this discussion.

Let’s look at each of these steps.

Stage 1 – Silent idea generation

In the first stage of Nominal Group Technique, the facilitator first explains the problem which the group needs to solve. Problem definition as well as the explanation has to be clear enough for all the participants. This will ensure the correct understanding of the problem. And thereby help come up with relevant ideas or solutions to solve the problem.

The first stage is about silent, individual idea generation. In this stage, you give sufficient time to the participants to come up with ideas and solutions on their own. The participants, individually think about the problem and come up with their own solutions. They can also use a notepad to jot down these ideas.

The participants should not talk to each other or discuss the solution at this stage. This is important because you do not want to influence the thought process of any participant. And you want everyone to contribute to the best of their capability. Plus, more heads thinking on their own, will generate more and diverse ideas.

This stage should not be for more than 15 or 20 minutes. Do remember, more time does not mean more ideas. If the participants can think of ideas, they will do so in the first 5 or 10 minutes itself. Extending the time for this session beyond 20 minutes will just waste time and not add any incremental value.

The facilitator ends stage one once the allotted time is over. And we move on to stage 2.

Stage 2 – Round robin idea collation

Stage 2 of Nominal Group Technique is the round robin stage for idea collation.

The facilitator puts up a chart paper on the whiteboard or the wall. Then she asks each participant to share one idea each and notes this idea on the chart. You follow the round robin method for this stage. Each participant shares only one idea. And then the facilitator moves to the next participant. And keeps listing down the ideas one after the other on the chart.

Again, no discussions at this stage. The participants only shares the idea and do not justify it or provide any explanation at this stage. This is again to avoid any bias or influence on others. We get sufficient time to discuss these ideas in the next stage, but not at this stage.

The participants are allowed to think about more ideas or solutions at this stage. While the group is sharing their ideas, others can think and come up with more ideas. However, they can not share these ideas as they come to them. They will need to wait their turn.

If a participant does not have an idea to share when his or her turn comes, they can chose to pass as well. The facilitator ends this step when all participants run out of ideas and have no more ideas to share.

Stage 3 – Clarification and discussion

The third step in Nominal Group Technique is to clarify and discuss the ideas generated. In this step, participants get a chance to clarify and expand on the ideas that they shared so that the group understands it better. The group discusses every idea at this stage. The idea owner explains their ideas and provide any clarifications needed.

The facilitator should be vigilant so as to not allow anyone to shoot down any idea. You should not eliminate any idea at this stage. The aim of the discussion is just to understand the ideas better.

You can also group similar ideas together, however, with acceptance from all the participants. The original idea owner can alter the ideas if needed post discussion.

Once everyone understands every idea that is listed, this step ends and we move to the next and final step of Nominal Group Technique.

By the way, do check out the Certified Lean Six Sigma Black Belt Handbook – it is one of the most essential guide for anyone trying to get certified as LSS Black belt or in general wants to understand LSS and improve processes. – check it out here.

Stage 4 – Voting (Ranking of generated ideas)

Step 4 in Nominal Group Technique is the multi-voting process for all generated ideas. In this step, each participant rates each idea on a predefined rating scale. The ratings describe the importance and/or relevance of the ideas in terms of solving the problem at hand. If a participant thinks a particular idea is very effective to solve the problem at hand, she rates it higher, and vice versa.

A point to remember. The facilitator should ensure that the group does not see each others ratings. The ratings are kept confidential till the voting process is complete. You do this step as an individual activity. This is to ensure that the ratings are not biased and participants do not influence each others ratings.

Ideally, the facilitator provides a list of ideas to each participant. The participants then rate each idea on the defined rating scale. The facilitator collects all these sheets when all the participants have rated all the ideas. And consolidates the ratings.

If you are using technology for this exercise, each participant can fill in their rating on a excel sheet and share the same with the facilitator who can then consolidate everyone’s ratings.

The facilitator sums up the ratings for each idea. This sum is called NGT score. The ideas are then ranked based on the NGT score. Ideas with highest NGT scores are selected as these are the ideas which the whole group thinks, are most relevant and effective to solve the problem at hand.

Relative ranking in Nominal Group Technique

Stage 4 of Nominal Group Technique warrants a detailed explanation. This stage gives you the final output from the exercise and it’s important its done correctly. Below are the steps you should follow to the the most relevant and effective solutions, as agreed by the group.

Step 1: Prepare Nominal Group Technique template for voting

The facilitator should list down all the generated ideas from step 3 above in the first column of NGT template. The next columns should have participants names as column headers. The last column is for the final NGT score for each solution. The template should look like the one shown below.

Step 2: Define NGT rating scale

You need to define the rating scale to be used for the exercise. It can be a simple discrete rating scale of 1 to 10 or 1 to 5. In such a scale, higher the impact or relevance of the solutions, higher should be the rating. And vice versa.

In this example, we will use the scale of 1 to 5 for simplicity. Here a rating of 5 means the solutions will very effectively solve the problem at hand. A rating of 1 will mean that the solution is irrelevant and does not solve the problem at hand.

Step 3: Ask participants to rate each solution

The facilitator then ask each participant to rate each solution, using the rating scale as defined above. This exercise needs to be done individually by each participant. The ratings from the participants should be kept absolutely confidential and not to be shared with others to avoid bias.

Once this step is done, the NGT template with the facilitator will look similar this.

Step 4: Calculate NGT score

Once the facilitator collates the ratings from each participant for all solutions, its time to calculate the NGT score. This is the sum of ratings from all participants for each individual idea. The updated template looks like below.

Step 5: Define NGT threshold

NGT threshold is the value for NGT score above which you will treat the solution as relevant and prioritize for implementation.

As a thumb rule, the NGT threshold should be half the maximum possible NGT score.

Lets assume, you have 6 participants in the NGT exercise. And you are using a rating scale of 1 to 5. Hence, the maximum rating a participant can give to a solution is 5. If all 6 participants give the maximum possible rating to a single solution, you get the maximum possible NGT score of 6 X 5, that is 30.

Half of this maximum possible NGT score (15) is your NGT threshold.

Step 6: Shortlist solutions

Now that you have the NGT threshold as well as the NGT scores for each solution, you can go ahead and shortlist solutions from the list.

All solutions with NGT score above the NGT threshold (15 in our example) should be shortlisted.

Please remember, these are thumb rules. You can set up a different NGT threshold depending on your situation and needs.

When to use Nominal Group Technique

Nominal Group Technique or NGT can be effectively used when

• Some group members are much more vocal than others
• Some group members think better independently / individually / peacefully
• Few group members are known to be not participating
• The group does not easily generate ideas, solutions
• The group is new or few members in the group are new
• The issue at hand is controversial leading to a heated discussion

That’s all about Nominal Group Technique for now. I hope this helped.

For further reading, do click here to know how CDC uses Nominal Group Technique to gain consensus among its stakeholders and click here to read through University of Arkansas’s white paper on Nominal Group Technique. (opens in new tab)

If you have used NGT in any context during your career, I would love to hear about the experience, both good and bad 🙂 Do share your experience in the comment section below so all the readers can benefit.

Sachin Naik

Passionate about improving processes and systems | Lean Six Sigma practitioner, trainer and coach for 14+ years consulting giant corporations and fortune 500 companies on Operational Excellence | Start-up enthusiast | Change Management and Design Thinking student | Love to ride and drive

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