GA4: Enhanced Measurement

Google Analytics 4 offers some interactions that are tracked without the need to change the website’s code or configure a GTM container.
That auto-tracking feature is called Enhanced Measurement.

Event tracking in GA4
Enhanced Measurement is a part of event tracking in GA4.
There are also recommended events and custom events.

Speaking of automatic events (but excluding enhanced measurement), there are some additional events that GA4 tracks automatically as well. See the list here.

The list of automatic website events:
1. first_visit.
This is the first time a user visits a website or launches an app.

2. session_start.
When a user engages the app or website and starts a new session.

3. user_engagement. This event is fired 10 seconds after the visitor has stayed on a page. 

The page_view event is added into the Enhanced Measurement feature.

Enhanced Measurement in GA4
Enhanced Measurement is a suite of automatic event-tracking features that allows marketers/analysts to collect more data out of the box. In the UA, only pageviews existed. 

During a web data stream's configuration in Google Analytics 4, we can use Enhanced Measurement. 
Go to Admin > Data Streams > Select the web data stream > Enhanced Measurement

By default, this feature is enabled and will automatically track the following events:
- Page view (event name: page_view)
- Scroll (event name: scroll)
- Outbound link click (event name: click with the parameter outbound: true)
- Site search (event name: view_search_results)
- Video Engagement (events: video_start, video_progress, video_complete)
- File Download (event name: file_download)

We can disable/enable events individually by clicking the gear icon in the Enhanced Measurement section.

Page views
When the page view is sent to GA4, the event name is page_view. 
Page views cannot be turned off in Enhanced Measurement.

Every event tracked with GA4 (client-side) tracks also contains several parameters (they also apply to custom events):
- language
- page_location
- page_referrer
- page_title
- screen_resolution

Scrolls
When a visitor scrolls below 90% of the page height, a scroll event is sent to GA4.
If you want to add some additional thresholds (such as 25%, 50%, etc.), you can’t do that in Enhanced Measurement.
If you want to track additional thresholds, you can disable that feature in GA4 and then send scroll events configured in GTM.

Outbound clicks
When a visitor clicks a link on your website and that link redirects a visitor to another domain, this is considered as an outbound link click.

An additional parameter outbound (with value “true”) is sent with this event.
The event with this parameter means that there was an outbound link click.
Together with this event, a bunch of other parameters is sent:
- link_classes
- link_domain
- link_id
- link_url
If a business operates on several domains, go to Tagging Settings (of that very same event stream) > Configure your domains and then enter the domains of the business.
All the domains that are listed there will not trigger the outbound link click event.

In order to see/use link_classes, link_domain, link_id, link_url in the GA4 reports, we need to register them as custom dimensions.


Video Engagement
Enhanced Measurement is capable of tracking interactions of the embedded Youtube video on the website and then sends “video_…” events to GA4.
But those embedded Youtube video players must contain the ?enablejsapi=1 parameter in their URL.

Because of those nuances, this automatic video tracking will not work in many cases so check this and this article in order to do it via GTM.

Video tracking with Enhanced Measurement
Events that are automatically captured:

- video_start.
Sent when a visitor starts watching a video.

- video_progress.
When a viewer reaches a particular threshold of the video (10%, 25%, 50%, 75%).

- video_complete.
When a visitor reaches the end of the video.


Parameters that are automatically tracked by this feature:

- video_current_time.
The current timestamp of the video where the viewer is at (in seconds)

- video_duration.
Video duration in seconds.

- video_percent.
The threshold of the video (without the % sign)

- video_provider.
The value of this parameter is always “youtube”.

- video_title.
The title of the video.

- video_url.
This is the URL of the video.

- visible.
Returns “1” if the player is visible on the screen while the video engagement was tracked.

In order to use/see any of these in GA4 reports, we need to register them as custom definitions.