After reaching the end of a marketing campaign, how do you know if your efforts made a difference? Can you simply take credit for all those sales? Can you assure yourself that the sales truly happened due to your marketing?
One method we insist on using at Hacker Group is a never-mailed control group – a group that lets you stay in control of your results and take credit where you deserve. A control group allows you to see what a similar group will do under similar circumstances without the treatment or marketing effort you are applying.
One of our clients recently released a very hot product that resulted in a large spike in sales in May and June of this year. We ran many campaigns that spanned that time period and, without a control group, our sales curve would have shown a very healthy spike in sales around that time – for all campaigns – even those not offering this product. The control group allowed us to view the natural spike in sales for what really caused it – and only take credit for the results we produced.
There are five considerations for building a control group:
1) It is very important that a control group is set aside before the campaign begins, as once the group gets touched by the direct marketing effort, it cannot be used for a control group.
2) A control group needs to be representative of the targeted group as a whole. If possible, use the group you are targeting as the source of your control group. Take a random sample (at least 10%) and hold them out.
3) Create a large enough control group that you are able to perform similar tests and analyses on it as you are going to do on your mail group.
4) Track your control group during the same time period as your mailed group. There are many factors happening out in the market and seasonal variables can make a big difference.
5) Decide whether you will use your control group for multiple campaigns or only this one. If you decide to reuse your control group, be sure that it will be representative over time and for all groups.
Realize that the lost opportunity of mailing to the control group is a cost, but one that is well worth the value of getting accurate and reliable results that you can attribute to your direct marketing efforts.