International Standard Serial Numbers (ISSNs) in References (APA style)? Question

When, if ever, do you include an ISSN in a references entry; and if you do, then in what form to comply with APA style?

Background

International Standard Serial Numbers (ISSNs) are used to uniquely identify serial publications, and the numbers can be helpful in distinguishing between publications that have the same or similar titles. 

I am editing a dissertation and don't know how to advise the author about when, whether, or how to include an ISSN in a reference.

As best I can deduce from perusing the APA Manual 6th edition and searching the apastyle blog, there are no circumstances where you include an ISSN. 

But is that so? If it helps, the author of the paper included this entry:

Getkin, K. (2009). Reforming or changing educational leadership. The Journal for Quality and Participation, 32(2), 15-19. ISSN 10409602.

Note: I posted a question about this on the apastyle blog in December 2018 and followed up in January. No one seems willing to tackle the question ...)
Since the ISSN refers to the journal, it isn't a very precise identifier for a publication in the journal. I'd highly recomment to use the DOI instead, if availble. This is becoming more and more a common convention in science. Listing the ISSN is in contrast relatively rare.