How To Use Control Groups

Have you ever wondered, is my email campaign really effective? Like many marketers, these answers are not always straightforward, which is why control groups are utilized. Control groups help us determine what is useful and what is not. For ages, control groups have been used in science to identify effectiveness of medications, procedures, and much more. Control groups are a method of comparing. They help us become better people and marketers! Not every idea or strategy is going to produce great results, so it is important to know what to invest your time and money in. All good marketers conduct research indefinitely.

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Modifications and Testing

The world around us is changing every day and these modifications need to be accounted for. When you think about advertising, promotional efforts have shifted extensively over the last 20 years in response to digital demand. If businesses continued traditional marketing, it would be a waste of money, and customers would be negatively impacted. This is where control groups come into play. They help us learn and improve our efforts to ensure we are serving our customers to the best of our ability and gaining something on these actions. To better understand control groups, this article is going to dive into what control groups are, why it is important to have, and the overall purpose of having one.

What are Control Groups?

First things first, what in the world are control groups? A control group is a group of people who are not exposed to the important part of a test being performed. For marketing purposes, control groups are used to measure the effectiveness of a campaign and the overall outcome. Control groups consist of the customers you are targeting who are not exposed to the campaign you are testing. For years, control groups have been utilized to determine the outcome of an action of a test treatment. Control groups in marketing is the same concept learned in science in elementary school. The next time you ask yourself, what are control groups, think back to the plant experiment you did in 5th grade where one plant received special lighting and the other did not. The plant that did not is the control group. All different aspects of marketing can be tested using a control group. Ad campaigns, keywords, email campaigns, and so much more can all be tested.

Landing Pages

Thinking about adding more features to your landing page? Test it out with a control group. For starters, a landing page is the webpage you get redirected to when you click on a link. This can come from an email or from your search results page. The ad copy (The copywriting of advertisements) should match the landing page content, otherwise your website will experience a high bounce rate. For example, if your ad copy showcases blue shoes on sale, your landing page should consist of those exact blue shoes on sale, so the customer does not have to navigate to try and find that page. When a customer clicks on a link, if the landing page does not match the initial ad copy, more than likely they will leave the website, making you incur an extra click cost and no conversion.

customer service

Strategic Placement

Cost-per-click can get expensive if you are not strategic about it, which is why capitalizing on control groups in this scenario is extremely useful. If you want to add more graphics to your landing page to showcase the product, you could create a different landing page and send an email out to half your list with the new landing page, and the other half the original. After a period of time, you can measure impression rate, conversions, and bounce rate from each to determine whether or not the graphics enhanced your idea. A high bounce rate indicates that the page offered was inconsistent with the consumer’s intent. When you run cost-per-click ads, a high impression rate is not always a good thing. If the customer is clicking on your ad and then leaving the page, you are incurring costs from the click without a conversion, meaning you are receiving no return or revenue. Control groups can prevent this.

Email Marketing

Another component of marketing you can test using control groups is your email campaign. Email is the preferred method of contact for customers by far. Emails are an inexpensive way to advertise both your products and your brand. The most crucial aspect of an email is the subject line. This is going to drive the open rate and the attention the email receives. The subject line should be captivating, yet simple and straightforward. It should tell the customer exactly what to expect from the email. For example, if the purpose of the email is to build awareness about a month-long sale, the subject line should encompass that idea.


If you want to see the effectiveness of sending a coupon with the weekly email, you can send out two different emails: the original one, following your normal format and without the coupon (the control group), and another email to a different group of customers with the coupon. After a period of time, you can measure the open rate, click-through-rate, and ROI and measure your results.

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Why is it Important to Have a Control Group?

Understanding why it is important to have a control group is key. Control groups help marketers measure the incremental impact of a marketing campaign. If you choose to ignore control groups, you will never be able to measure the success of your strategies and actions taken.


For starters, control groups give you a reason to keep researching. Remember, research and marketing go hand and hand. You cannot be successful in marketing without the use of research. If your experiment reveals ineffective results, you have to keep trying until you see improvement. Marketing is about telling a story about your brand and products you offer. If you are poorly executing your story, no one is going to buy it.


Next, control groups help give structure. It makes employees feel inclined to think outside the box which develops into a good habit. Companies need to challenge themselves and their strategy constantly, and control groups help to challenge current ideas and spark new ones. When asking yourself, why is it important to have a control group, think about how much change the world experiences every day. You have to be open to change and that starts with testing ideas.

Cost Effective

Control groups can also help to prevent cannibalization. Cannibalization happens when customers are not exposed to promotions or advertising but purchased your product anyways. In this case, you have the opportunity to allocate your advertising elsewhere. You certainly do not want your money to go to waste.

customer control group

What is the Purpose of a Control Group?

When you think about what the purpose of a control group is, think about the progress your company has made, or the progress you want it to make. Without challenging your business and performing tests, you would not be able to compete with a rapidly changing consumer behavior. You might think, well last time I just took a leap of faith and it ended up helping my business, so what is the purpose of a control group? The answer is in the word, control. It literally gives you control over your business and its strategy. Instead of guessing what is going to help you reach your goals, control groups tell you flat out.

Unforeseen Events

We live in an instantaneous society where preferences are constantly changing, and everyone is trying to be the best. A competitor can release a new campaign that will make your campaign look less attractive. In response to drastic changes in the market, control groups help you respond efficiently. You can use incentives to respond to competitor’s actions and retain your consumer base.

Refrain from Redundancy

Customers get tired of seeing the same stuff week after week because it is boring. The purpose of a control group is to avoid repeating the same offers over and over again. You want to keep your consumer engaged, and that means offering fresh content they have never seen. This will help differentiate you from competitors too. Sometimes this means segmenting your audience into small parts based upon preferences and behavior. Other times, you just need to test out unique content that might end up being extremely interactive and gives you the result you want.


Improve your Marketing Strategy Today

Creating a great marketing strategy begins with your willingness to explore various options and invest in your strategy. Marketing is the backbone of the company, because it tells people who you are and what you do. Brand loyalty is a direct result of a good marketing plan and proper implementation. First, you want to acquire the customer, but the act of retaining them is just as important and is probably the hardest part. Between all of the different alternatives that are readily accessible in the click of a button, your marketing strategy needs to be strong and constantly challenging the norms. For help with integrating control groups and further developing your marketing strategy, contact SEO Design Chicago today!


  • What is a bounce rate?
  • What is a landing page?
  • Are there different aspects of marketing that can be tested with a control group?
  • How can you achieve increased brand loyalty?
  • What is business cannibalization?

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