Does scroll search sorted by _doc calculate scores?

In early Elasticsearch versions, there existed the search type "Scan", which was deprecated in 2.1 "in favour of regular scroll requests sorted by _doc ."

Quoting the documentation for version 1.7 (emphasis mine):

Scrolling can be combined with the scan search type to disable any scoring or sorting and to return results in the most efficient way possible.

A scroll request sorted by document index order is the successor of the scan search type. From what I have read, it skips the sorting of the search results. But I have found no information about whether it also disables scoring.

Does a scroll search sorted by _doc calculates scores? And if so, is it advisable to use an explicit filter context?