That is only one type of control group. There are at least three -- one of which is completely satisfied by this scenario.

Types of Control Groups:

• Placebo Control Group: Receives an inert treatment (like a sugar pill), which looks identical to the actual treatment but has no therapeutic effect. This helps to measure the placebo effect.
• Active Control Group: Receives an existing, standard treatment for the condition. This is used when it would be unethical to give a placebo because an effective treatment already exists.
• No Treatment Control Group: Receives no treatment at all, which can be used when the natural progression of the disease or condition is well understood and withholding treatment doesn't pose ethical issues.