What are the four scope levels available for dimensions and metrics in Google Analytics?
Location-level, duration-level, product-level, or user-level scope
Event-level, duration-level, transaction-level, or user-level scope
Hit-level, session-level, product-level, or user-level scope
Event-level, session-level, transaction-level, or user-level scope
Scope determines which hits will be associated with a particular custom dimension value. There are four levels of scope: product, hit, session, and user:
- Product – value is applied to the product for which it has been set (Enhanced Ecommerce only).
- Hit – value is applied to the single hit for which it has been set.
- Session – value is applied to all hits in a single session.
- User – value is applied to all hits in current and future sessions, until value changes or custom dimension is made inactive.
Read more here: https://support.google.com/analytics/answer/2709828#scope
Custom dimensions and metrics allow you to combine Analytics data with non-Analytics data, e.g. CRM data. For example:
If you store the gender of signed-in users in a CRM system, you could combine this information with your Analytics data to see Pageviews by gender.
If you’re a game developer, metrics like “level completions” or “high score” may be more relevant to you than pre-defined metrics like Screenviews. By tracking this data with custom metrics, you can track progress against your most important metrics in flexible and easy-to-read custom reports.
Custom dimensions can appear as primary dimensions in Custom Reports. You can also use them as Segments and secondary dimensions in standard reports.
Custom dimensions and metrics are only available for properties that have either been enabled for Universal Analytics or contain at least one app reporting view. Custom dimensions and metrics are supported by the Google Analytics SDKs for Android and iOS v2.x or higher, analytics.js, and the Measurement Protocol.
Custom dimensions and metrics require additional setup in your Analytics account and in your tracking code. Once you complete both steps of the setup, you can use them in your reports.
Limits and caveats
There are 20 indices available for different custom dimensions and 20 indices for custom metrics in each property. 360 accounts have 200 indices available for custom dimensions and 200 for custom metrics.
Custom dimensions cannot be deleted, but you can disable them. You should avoid trying to reuse custom dimensions. When you edit the name, scope, and value of a custom dimension, both the old and the new values can be paired with the either the old or the new dimension name. This conflates data in your reports in a way that cannot be accurately separated with a filter.
Lifecycle of custom dimensions and metrics
The lifecycle of a custom dimension or metric has four stages:
Configuration – you define your custom dimensions and metrics with an index, a name, and other properties like scope.
Collection – you send custom dimension and metric values to Analytics from your implementation.
Processing – your data is processed using your custom dimension and metric definitions and any reporting view filters.
Reporting – you build new reports using your custom dimensions and metrics in the Analytics user interface.
Before you can send custom dimension and metric values to Analytics, they must first be defined in an Analytics property. Each Analytics property has 20 available indices for custom dimensions, and another 20 indices available for custom metrics.
When you define a custom dimension or metric, you specify its name and other configuration values at a particular index. Custom Dimensions have the following configuration values:
Name – the name of the custom dimension as it will appear in your reports.
Scope – specifies to which data the custom dimension or metric will be applied. Learn more about Scope.
Active – whether the custom dimension or metric value will be processed. Inactive custom dimensions may still appear in reporting, but their values will not be processed.
Custom metrics have the following configuration values:
Name – the name of the custom metric as it will appear in your reports.
Type – determines how the custom metric value will be displayed in reports.
Minimum / Maximum Value – the minimum and maximum values that will be processed and displayed in your reports.
Active – whether the custom metric value will be processed. Inactive custom metrics may still appear in reporting, but their values will not be processed.
Custom dimensions and metrics can be defined in the Analytics user interface.
Once you define a custom dimension or metric, avoid editing name or scope when possible. See Implementation Considerations to learn more about how changes to these values can affect your reporting.
Custom dimension and metric values are sent to Analytics at collection time as a pair of index and value parameters. The index parameter corresponds to the index of the custom dimension or metric defined in the Configuration phase.
Unlike other types of data, custom dimensions and metrics are sent to Analytics as parameters attached to other hits, like pageviews, events, or ecommerce transactions. As such, custom dimension or metric values need to be set before a tracking call is made in order for that value to be sent to Analytics.