A treatment group is the set of customers or leads who receive the marketing intervention being evaluated. Comparing its outcomes with a comparable control group helps distinguish campaign-driven uplift from outside influences. section 7.7.3
Randomly assign eligible participants to treatment or control, then expose only the treatment group. Keep participants in their original assignments for analysis, including those who do not complete the experiment; a well-designed activation architecture exports treatment members, not control members. section 3.2.1
Examples of treatment-group interventions include:
- Personalized email messaging compared with a generic subject line. section 7.7.3
- First-party-data lookalike targeting compared with broader, non-segmented targeting. section 7.7.3
- An added SMS sequence compared with email-only communications. section 7.7.3

