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CLT Study: Central Location Tests with Consumer Durables

January 23, 2020
Ashley Jefferson Author 8 mins read
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The Stevenson Company is very familiar with conducting Central Location Tests (CLT). We made our name conducting this type of study. A CLT study should follow the tried and true best practices of other research methodologies. Below we will provide areas of focus and pitfalls to avoid when conducting this type of study, specifically with consumer durable products.

What is a CLT Study?

Before we get into specifics, let’s back up and define a typical CLT study. CLT is a type of Consumer Usage Test (CUT) that is conducted in a predetermined location (typically a focus group room, hotel ballroom, hall, or similar venue). A main reason for conducting a CLT study is to put the test product(s) in front of consumers, as opposed to a product text description, rendering, or image that could easily be examined via an online survey. The in-person interaction of a CLT is particularly useful when a study’s objectives include feedback on functionality, usability, design, aesthetics, or product dimensions. In a CLT study with consumer durables, consumers are recruited upfront based on appropriate specifications. Typically, this means respondents match a target consumer profile, are current product owners, and/or are interested in purchasing the product soon. These recruits are then asked to arrive at the space at a specified time. The interview format can be a simple one-on-one interview, have several respondents at once like a focus group or mini group, or even dozens of participants at a time. The main factor is that respondents in a CLT are arriving at a predetermined location to examine study stimulus in-person.

Where should I conduct a CLT study?

The big picture: Geographic Location

One of the differences in a CLT as opposed to a more common online type study is where the sample will come from. By and large an online study will have participants from a wide area (regionally, nationally, or possibly internationally). With a CLT, respondents are coming to a predetermined location; which means participant travel is involved. You will be hard-pressed to find someone that agrees to drive 40 miles to the location. That means finding qualified respondents can be challenging, especially when recruiting for a consumer durable product where purchase incidence is less frequent than other product types (consumer packaged goods, for example). To account for that, you usually need to consider metro areas with a high population density. Chances are you want a sample size large enough to support cutting the data by consumer characteristics, product configurations, or other considerations. Recruiting from a high population metro area will provide a better chance of finding an adequate number of target recruits.

Let’s talk about venue

Another consideration is venue size: depending on what is displayed, a product layout that represents a typical retail setting is likely preferred. For instance, if the study goal is feedback on home appliances (let’s say refrigerators), a room layout that mirrors a high traffic retail store such as Lowe’s or Home Depot is a good choice. In the refrigerator example, that means a large room will be needed to effectively display products so that there is enough room for product interaction. This is especially true if the interview flow includes multiple participants at a time. You don’t want participants tripping over each other when trying to examine study stimulus.

More Room Specifics

Room type is also something to consider. If space needs allow for it, using a traditional focus group room works best. This gives the benefit of a one-way mirror for clients and facilitators to observe interviews in real time without impacting respondents or interview flow and allows for covert interview recording due to discreet camera placement. The downside is that focus group rooms are usually smaller than ballrooms. Due to their size, ballrooms or meeting halls give greater flexibility for room layout. However, a ballroom setup could have clients that want to observe sitting far away from the interview space and not close enough to appreciate subtle interactions or responses. Unlike focus group rooms, ballrooms also make interview recording a challenge, due to the obviousness of a recording device in the room. It’s a trade-off that should be considered.


Logistics, particularly product shipping, is something that needs to be considered. At first glance this may seem like a trivial concern. However, what happens if you spent all this time and money setting up a consumer durable CLT study and on start day your products don’t show on-time and in perfect condition? You’re in trouble. The whole point of a CLT is to get in-person respondent feedback. From the refrigerator consumer durable example mentioned earlier, you don’t want your refrigerators to arrive with dents or broken pieces. Participants in general will react to what they see. While some product blemishes can be dismissed as “overlook the shipping damage you see here,” you should consider hiring a professional moving team. It’s not the most cost-effective option, but it could spare you headaches down the road. After all, test products need to get from point A to point B on time and in good shape. Think of it as an insurance policy on the time and money spent to ensure study success.

Interview Flow, Set-up, and Schedule

Interview Flow

As mentioned earlier, the interview flow of a CLT study could be one-on-one, focus groups of 8-12 participants at a time, smaller sessions with 4-5 participants (usually quantitative in nature), etc. For a CLT study on general product development, improvement, or design/aesthetic topics, The Stevenson Company usually recommends a two-pronged attack:

  1. Quantitative, self-administered interviews with 4-5 respondents (depending on number of products) interacting with study stimulus.
  2. A handful of follow-up qualitative sessions with respondents (and the product) recruited from the previous quantitative interviews

The goal of these follow-up sessions is to add more color to previous responses and better define the “why” of their responses. Since follow-up recruiting is based on respondent’s previous responses, The Stevenson Company implements an electronic survey administered on iPads for the quantitative interviews. This allows real-time results and the ability to flag qualifying participants for a follow-up session immediately after the quantitative interview.

Interview Set-up and Scheduling

Interview scheduling should be carefully planned. If the study goal is to get a sample size adequate enough to allow data being cut on specific respondent/product characteristics, the CLT study won’t be completed in a day. How long is the survey?  How many interview sessions can be completed in a day?  How many follow-up focus groups are planned?  These questions need to be answered to plan how many days the field will last. The Stevenson Company typically conducts a consumer durable CLT with 150-200 quantitative completes and 3-4 focus groups in 4-5 days. This timing includes interview briefing and product setup. As a note, product setup with consumer durables can take anywhere from an hour to most of the day: plan accordingly.

Another scheduling factor to plan is product rotation. Not only should the respondent survey include rotating product examination order, the room itself should show products in a different order (to minimize order bias). Depending on the product type (we’ll go back to the refrigerator example), changing product order is not a trivial matter. It takes time to physically move refrigerators around a room. Be sure to allow time for one or two product order rotations per day.

Staffing needs

Study personnel is another detail to plan. Depending on survey flow, you may need just a few people, or several people may be needed. In the example above, with the “two-prong” study design, you will need at least three types of people:

  • Check-in staff. Someone to organize respondents as they arrive.
    • This person is usually provided by the recruiting company. They will need to help with respondent check-in, delivering reminder calls if needed, administering payment, and any pre or post interview activities.
  • Proctor(s) for the self-administered quantitative survey to guide the interview.
    • Doesn’t necessarily need to be a professional interviewer, e.g. a one-on-one interviewer or similar, but some experience with leading an interview is mandatory. Telephone interviewers usually work fine in this role, if they are comfortable speaking to small groups of people.
    • A typical CLT day can last 12 hours or more. It’s a long day, but the goal is to get efficient use of rental space costs. Therefore, it is smart to plan 2 or more shifts of proctors to avoid fatigue. That means multiple proctors will be needed.
  • Focus group moderator. This person can be provided/recommended by the recruiting company. However, The Stevenson Company prefers to work with tried-and-true moderators that are very familiar with the product category.

Overall, there are a number of important aspects to consider when planning and executing a consumer durables CLT. Even if you have run similar studies in the past, partnering with research providers who have a proven track record for CLT studies will help smooth over any challenges you may have with the project. If you’ve run a study like this before, what are other tips you’d pass on to first timers?  If you’ve never performed a CLT study, but are hoping to, contact our team!  We’ll be glad to get you pointed in the right direction.