"Result Click" and "Record View" are new metrics available with COUNTER Release 4. Result clicks count each time a user clicked a link from the search result to the detailed view, a link resolver, etc., while a Record View counts the abstract/detailed records explicitly viewed from the database.
These measures were introduced because they indicate an explicit expression of interest in the result and provide a more direct measure of database usage, in particular for A&I databases. These measures are available in Database Report 1 and Report 3.
In addition, "Sessions" are no longer considered a valid metric and are no longer included in COUNTER reports. This change was made due to an increase in stateless approaches in modern web technology and the rise in discovery service usage, which have led to Sessions no longer being considered a reliable metric for usage.