Overview

A System Control Group (SCG) is a workspace-level holdout. It keeps the same set of users out of every campaign and journey where you apply it. Because these users receive no marketing from those campaigns, their behavior shows your organic baseline. Comparing that baseline with users who do receive your messages shows how many additional conversions your marketing actually drives.

A custom control group holds users out of one campaign or journey only. Those users can still receive your other campaigns, so their conversions may still be influenced by marketing. A percentage-based custom control group is also selected separately for each campaign, so a user held out of one campaign can be in the target group of the next. The SCG removes this noise by holding out the same users everywhere you apply it.

Use the SCG to answer questions such as:

• How many conversions would you lose if you stopped marketing to a share of your users?
• Are your campaigns converting more users than would have converted on their own?
• Do on-site experiences, such as social proof, drive purchases even when users never click them?

System Control Group vs Custom Control Group

You can apply both to the same journey. Refer to Use the SCG with a Custom Control Group for details.

Use Cases

Why Use the System Control Group

• Measure what your marketing adds: Compare a consistent control group with a consistent target group to see the conversions your marketing creates beyond organic behavior.
• Count conversions that happen without a click: Track conversions from on-site messages and personalized content, where users often see content and purchase without clicking.
• Compare both groups fairly: Conversions for both groups are counted from the same starting point, which makes results easier to read and explain.
• Save setup effort: Set one holdout for the workspace instead of configuring a control group for every campaign and journey.

Uplift

Uplift is the metric that shows the incremental impact of your marketing. It compares the conversion rate of users who were held out, the control group (CG), with users who received the campaign, the target group (TG).

How Uplift Is Calculated

Uplift % = ((TG conversion rate - CG conversion rate) / CG conversion rate) x 100

A positive uplift means users who received your marketing converted at a higher rate than users who did not.

The uplift formula is the same for every channel. What changes is the point from which conversions are counted, which depends on whether the channel is a push channel or a pull channel.

Push Channels

Netcore sends push campaigns to users. Conversions are counted from the time the campaign is sent.

TG conversion rate = TG conversions after the send / TG users the campaign was sent to
CG conversion rate = CG conversions / CG users who qualified and were held out

Pull Channels

Pull campaigns are shown when the user visits your app or website. Conversions are counted from the time the campaign is viewed.

TG conversion rate = TG conversions after the view / TG users who viewed the campaign
CG conversion rate = CG conversions / CG users who qualified and were not shown the campaign

For control group users in pull channels, the count starts when the trigger event qualifies them, such as an app open or a page load, because the campaign is not shown to them.

Journeys

In a journey, both groups are counted per journey entry. Only entries that reach the first action node are counted. Refer to How Control Group Users Move Through a Journey for details.

TG conversion rate = TG conversions / TG entries that reached the first action node
CG conversion rate = CG conversions / CG entries that reached the first action node

Uplift Conversion Check

Your existing conversion and revenue metrics use last-click attribution. A conversion counts only when the user clicks a message before converting. Control group users receive nothing to click, so a last-click comparison between the two groups is not fair.

For uplift, Netcore counts every conversion from the moment a user qualifies for a campaign, whether or not the user clicked. The way the control group is counted does not change. Only the target group is counted differently, so that both groups start from the same point.

Example

A campaign qualifies 10,000 users. The control group holds out 1,000 of them, and the campaign is sent to the remaining 9,000.

The CG conversion rate is 32 / 1,000 = 3.2%.

• With last-click conversions, the TG rate is 260 / 9,000 = 2.9%. The 136 purchasers who did not click are left out.
• With uplift conversions, the TG rate is 396 / 9,000 = 4.4%. Uplift is ((4.4 - 3.2) / 3.2) x 100 = 37.5%, displayed as 38%.
  This example shows how the two methods count conversions differently. It does not mean uplift is always positive. Your results depend on how your campaigns perform.

Delay Uplift

• Uplift appears for campaigns and journeys that have a control group enabled. This includes those that use only a custom control group.
• Uplift is rounded up to the next whole number. For example, 15.1% is displayed as 16%.
• Negative uplift is displayed as is. It means the control group converted at a higher rate than the target group.
• Uplift is shown at the campaign and journey level. It is not shown for individual messages.
  Refer to View Uplift in Reports to see where uplift appears in the panel.

Uplift Stats VS Last Click-Through Conversions

The question is when to Refer to Uplift Stats and When to Use Last Click-Through Conversions. Uplift stats and last click-through conversions answer different questions, so you can use both. Which one fits depends on how often you review your campaigns and what you want to learn.

Last click-through conversions work well for optimizing individual campaigns. For ROI, they have a limit: they show only conversions that followed a click, not how many conversions your marketing added overall. The Netcore revenue contribution you see today is also based on last click-through conversions.

The SCG fills this gap. With a consistent control group and conversions counted from the send or the view instead of the click, you can measure the incremental impact of everything you run through Netcore, across campaigns, channels, and personalization.

Create a System Control Group

Log in to the Netcore CE panel and navigate to Analytics > Control Group. Open the System tab.

1. Click Create. The create panel opens on the right.
2. Under user allocation, select By percentage.
3. Use the slider to set the percentage of users to hold out. The default is 5%.
4. Optionally, select Apply to existing campaigns and journeys which have control group enabled. Use this option to add the SCG to campaigns and journeys that are already scheduled or running. Refer to the table below for the statuses it covers.
5. Click Save.

   Type	Applies to All Statuses Except
   Journeys	Completed and Archived
   Campaigns	Failed
   On-site messages	Suspended and Archived
   Personalized content	Completed

The SCG takes up to 24 hours to become active. You receive an in-app notification when it is ready.

View System Control Group

The System tab shows the details of your SCG:

Click Download users to download the list of users in the SCG.

How Users Are Selected

Netcore selects SCG users at random from your user base using a stable method:

• Users stay in their group. A user in the SCG stays in the SCG, and a user outside it stays outside it. Groups are not reshuffled over time.
• New users are included automatically. Each new user is evaluated the same way, so the SCG stays close to your chosen percentage as your user base grows.
• Deleted users reduce the count. The SCG shrinks naturally when users are deleted or merged.
• Identified and anonymous users are held out separately. Your chosen percentage applies to each group, so neither is over or under represented.

Apply the SCG to a Campaign or Journey

The SCG applies only to campaigns and journeys where you select it. Creating an SCG does not change any campaign or journey on its own.

1. While creating a campaign or journey, go to the Control Group section.
2. Select Apply system control group.
3. Optionally, select Apply custom control group and choose a custom control group.
   Click View your global settings to see the SCG configured for your workspace.

The options available depend on where you are applying the control group:

When Holdout Percentage Is Not Shown in a Campaign

The SCG holds out a percentage of your whole user base, not of each campaign. Only SCG users who qualify for a campaign are held out of it, so the share held out in a given campaign can be higher or lower than your chosen percentage. For example, a 5% SCG in a base of 100,000 users holds out 5,000 users. A campaign that qualifies 1,000 users holds out only those SCG users who are among the 1,000.

Use the SCG with a Custom Control Group

When you select both, Netcore checks each user in this order:

1. If the user is in the SCG, the user is held out.
2. If not, Netcore checks the custom control group. If the user is selected, the user is held out.
3. All remaining users receive the campaign as the target group.
   A user who belongs to both groups is held out once and counted once. For example, if two users are in the SCG and the custom control group contains those two plus two others, four users are held out in total. Uplift combines users from both control groups into a single CG.

Send Important or Transactional Messages

Applying the SCG is optional for every campaign and journey. For service, transactional, or reactivation messages that SCG users must receive, leave Apply system control group unselected. The panel displays the message This campaign will be sent to users in the System Control Group to confirm that SCG users will receive it.

Journeys tagged as Transactional bypass DND, frequency capping, and control groups together.

If the SCG Is Deleted

The Apply system control group option is disabled in every campaign and journey. Hover over it to see the next step:

• Admins see a prompt to create a new SCG.
• Other users see a prompt to contact their admin.

When Users Are Evaluated

Netcore checks whether a user belongs to the SCG before any message is sent or shown.

Users held out by a control group are counted in the CG. They are not counted as failed or dropped sends. In journeys, users who exit before reaching the first action node are not counted in either group.

How Control Group Users Move Through a Journey

Control group users do not leave a journey at entry. They move through it the same way as target group users until the first action node, which is the first channel or campaign node in the journey.

1. The user enters the journey.
2. The user is evaluated for every condition before the first action node, such as filters, waits, and splits. If the user does not meet a condition, the user exits the journey and is not counted in either group.
3. When the user reaches the first action node, Netcore checks the control group. A control group user is dropped from the journey at this node and counted in the CG. A target group user receives the communication and continues the journey.

   📘

   Why Control Group Users Pass the Same Conditions

   Control group and target group users go through the same conditions before the first action node. Both groups therefore contain only users who would have received the communication, which keeps the comparison fair.

Edit or Delete the System Control Group

Change the Holdout Percentage

1. Open the System tab and edit the SCG.
2. Move the slider to the new percentage and click Save.
   The updated SCG moves to Processing, and the current SCG keeps applying until the update is active. After activation:

• New journey entries and campaign sends use the new percentage.
• Users already in a journey keep their original CG or TG group for reporting.
• If the SCG applies to active journeys, users who newly fall into the SCG and are waiting in a wait node exit the journey before their next communication. They are not re-entered automatically. If they trigger the journey again, Netcore evaluates them again at that point.
• If you lower the percentage, users who leave the SCG start receiving campaigns again.

  👍

  Good to Know

  Keep your holdout percentage stable for the whole period you want to measure. Changing it midway makes results before and after the change harder to compare.

Delete the SCG

1. Open the System tab and click Delete.
2. Review the confirmation message and confirm.

   🚧

   Before You Delete

   Deleting the SCG releases all users it holds out. These users become eligible for every campaign and journey they qualify for. Historical uplift reports remain available, but results before and after deletion may not be comparable.

View Uplift in Reports

Uplift appears on campaign and journey listing pages, in the journey detailed summary report, and in personalized content reports. Refer to Uplift to learn how it is calculated and displayed.

Campaign and Journey Listing Pages

The listing page shows an Uplift column after Conversion and Revenue. Uplift follows the selected date range. Hover over the info icon next to Uplift to see how it is calculated.

Click the uplift value to see the breakdown for each group:

Journey Detailed Summary Report

A one-time download of the journey detailed summary report includes these columns by default:

For scheduled downloads, select which of these columns to include. This keeps the file layout stable for any automated system that reads the report.

Personalized Content Reports

The campaign-level uplift appears beside Total Revenue and follows the selected duration. Each audience section shows its own uplift. The individual CG and TG rows inside an audience section do not show uplift.

Troubleshoot and FAQs

Q. Why is uplift not showing for my campaign?

A. Uplift appears only when the campaign or journey has a control group enabled and a conversion goal configured. If you just created the SCG, it may still be in Processing. It can take up to 24 hours to become active.

Q. Why is uplift different from my conversion numbers?

A. Uplift counts every conversion within the conversion window, whether or not the user clicked. Your existing conversion metric counts only conversions that follow a click. The two numbers measure different things.

Q. Why is uplift not the difference between the two conversion rates?

A. Uplift shows how much higher the TG conversion rate is compared with the CG conversion rate, as a percentage of the CG rate. Refer to Uplift for the formula and an example.

Q. What does negative uplift mean?

A. The control group converted at a higher rate than the target group for that period. This can point to message fatigue, poor targeting, or a sample that is too small to be reliable.

Q. Does the SCG set a conversion goal for my whole workspace?

A. No. The SCG decides only who is held out. Each campaign and journey keeps its own conversion goal, and uplift is calculated against that goal.

Q. Can I still send a campaign to SCG users?

A. Yes. Applying the SCG is optional for each campaign and journey. Leave Apply system control group unselected for campaigns that SCG users must receive, such as transactional or reactivation messages. Journeys tagged as Transactional also bypass control groups.

Q. Why is the share of users held out in my campaign different from my SCG percentage?

A. The SCG percentage applies to your whole user base. Only SCG users who qualify for a campaign are held out of it, so the share held out varies from campaign to campaign.

Q. What happens if a user is in both the SCG and a custom control group?

A. The user is held out once and counted once in the control group.

Q. Is uplift based on sent, delivered, or viewed messages?

A. Sent, for push channels such as Email, SMS, and App Push. For pull channels such as On-Site and Personalized Content, uplift is based on views. Using delivery would let channel and vendor delivery failures distort the comparison between the two groups.

Q. Is uplift calculated if I use only a custom control group?

A. Yes. Uplift is calculated whenever a campaign or journey has a control group enabled, whether it is the SCG, a custom control group, or both.

Q. Why did the number of users in my SCG change?

A. New users are evaluated automatically, and deleted or merged users are removed. The SCG stays close to your chosen percentage as your user base changes.

Q. Can I create the SCG from a list or a segment?

A. Not at present. The SCG supports allocation by percentage.

Q. Can I see which users are in the SCG?

A. Yes. Click Download users in the System tab to download the list of users in the SCG.

Q. Why are control group stats missing for a journey that was running before this feature was enabled?

A. Uplift and control group stats are calculated only from the date the feature is enabled for your account. Historical data is not recalculated. For a journey that was already running, stats appear only for activity after that date.